1657:
1621:
1192:: Feldspars are used in the ceramic industry as a flux to form a glassy phase in bodies during firing, and thus promote vitrification. They also are used as a source of alkalies and alumina in glazes. The composition of feldspar used in different ceramic formulations varies depending on various factors, including the properties of the individual grade, the other raw materials and the requirements of the finished products. However, typical additions include: tableware, 15% to 30% feldspar; high-tension electrical porcelains, 25% to 35%; sanitaryware, 25%; wall tile, 0% to 10%; and dental porcelain up to 80% feldspar.
1577:
1605:
1593:
942:
1561:
3348:
40:
978:
966:
954:
3336:
340:
935:
as long chains of aluminosilicate tetrahedra, sometimes described as crankshaft chains because their shape is kinked. Each crankshaft chain links to neighbouring crankshaft chains to form a three-dimensional network of fused four-member rings. The structure is open enough for cations (typically sodium, potassium, or calcium) to fit into the structure and provide charge balance.
2765:
1728:
1100:. Hydrolysis of feldspars begins with the feldspar dissolving in water, which happens best in acidic or basic solutions and less well in neutral ones. The speed at which feldspars are weathered is controlled by how quickly they are dissolved. Dissolved feldspar reacts with H or OH ions and precipitates clays. The reaction also produces new
1656:
1130:
Feldspars, especially plagioclase feldspars, are not very stable at the Earth's surface due to their high formation temperature. This lack of stability is why feldspars are easily weathered to clays. Because of this tendency to weather easily, feldspars are usually not prevalent in sedimentary rocks.
934:
The structure of a feldspar crystal is based on aluminosilicate tetrahedra. Each tetrahedron consists of an aluminium or silicon ion surrounded by four oxygen ions. Each oxygen ion, in turn, is shared by a neighbouring tetrahedron to form a three-dimensional network. The structure can be visualized
909:
Intermediate compositions of exsolve to two feldspars of contrasting composition during cooling, but diffusion is much slower than in alkali feldspar, and the resulting two-feldspar intergrowths typically are too fine-grained to be visible with optical microscopes. The immiscibility gaps in the
1147:
Feldspar is a common raw material used in glassmaking, ceramics, and to some extent as filler and an extender in paint, plastics, and rubber. In the US, about 66% of feldspar is consumed in glassmaking, including glass containers and glass fibre. Ceramics (including electrical insulators,
1620:
1036:
was introduced in the 18th century as a more specific term, referring perhaps to its common occurrence in rocks found in fields (Urban BrĂźckmann, 1783) or to its occurrence as "fields" within granite and other minerals (RenĂŠ-Just HaĂźy, 1804). The change from
711:
Barium feldspars form as the result of the substitution of barium for potassium in the mineral structure. Barium feldspars are sometimes classified as a separate group of feldspars, and sometimes they are classified as a sub-group of alkali feldspars.
667:
in the melt at low temperatures, therefore intermediate compositions of the alkali feldspars occur only in higher temperature environments. Sanidine is stable at the highest temperatures, and microcline at the lowest.
1236:
estimated global production of feldspar in 2020 to be 26 million tonnes, with the top four producing countries being: China 2 million tonnes; India 5 million tonnes; Italy 4 million; Turkey 7.6 million tonnes.
573:
of igneous rock. Calcium-rich plagioclase is the first feldspar to crystallize from cooling magma, but the plagioclase becomes increasingly sodium-rich as crystallization continues. This defines the continuous
586:
Alkali feldspars are grouped into two types: those containing potassium in combination with sodium, aluminium, or silicon; and those where potassium is replaced by barium. The first of these include:
1576:
480:, silicate minerals in which silicon ions are linked by shared oxygen ions to form a three-dimensional network. Compositions of major elements in common feldspars can be expressed in terms of three
680:
can be seen with the naked eye. Microperthitic textures in crystals are visible using a light microscope, whereas cryptoperthitic textures can be seen only with an electron microscope.
1135:
a short distance in cold and/or dry conditions that did not promote weathering, and that it was quickly buried by other sediment. Sandstones with large amounts of feldspar are called
1131:
Sedimentary rocks that contain large amounts of feldspar indicate that the sediment did not undergo much chemical weathering before being buried. This means it was probably
1604:
2787:
2646:
2708:
1592:
558:, or, more properly, plagioclase feldspar. Only limited solid solution occurs between K-feldspar and anorthite, and in the two other solid solutions,
1963:"Magma Mixing and Crustal Recycling Recorded in Ternary Feldspar from Compositionally Zoned Peralkaline Ignimbrite A', Gran Canaria, Canary Islands"
1709:
941:
1894:
676:
of contrasting alkali feldspar compositions during cooling of an intermediate composition. The perthitic textures in the alkali feldspars of many
2056:
2750:
2520:
2490:
2436:
1945:
1560:
2626:'Industrial Minerals & Rocks - Commodities, Markets And Uses' J. E. Kogel. Society For Mining, Metallurgy And Exploration, 2006. Pg. 458
1061:, has fallen out of use. The term 'felsic', meaning light coloured minerals such as quartz and feldspars, is an acronymic word derived from
2817:
1849:
1686:
910:
plagioclase solid solutions are complex compared to the gap in the alkali feldspars. The play of colours visible in some feldspar of
2394:
2190:
2040:
1904:
1877:
394:
977:
965:
953:
2164:
1746:
2230:
228:
1127:. Feldspar that has been replaced by clay looks chalky compared to more crystalline and glassy unweathered feldspar grains.
2014:
261:
44:
Feldspar crystal 18 cm Ă 21 cm Ă 8.5 cm (7.1 in Ă 8.3 in Ă 3.3 in) from
3394:
3389:
3339:
3308:
3384:
2415:
562:
occurs at temperatures common in the crust of the Earth. Albite is considered both a plagioclase and alkali feldspar.
1732:
1920:
Rudnick, R. L.; Gao, S. (2003). "Composition of the
Continental Crust". In Holland, H. D.; Turekian, K. K. (eds.).
575:
554:
between K-feldspar and albite are called alkali feldspar. Solid solutions between albite and anorthite are called
3323:
2611:
1737:
20:
3318:
1714:
1178:
for glassmaking, feldspar is valued for its low iron and refractory mineral content, a low cost per unit of Al
3379:
2810:
2651:
169:
2716:
2542:
2113:
1199:
481:
1627:
1583:
218:
2769:
2105:
2053:
1974:
1925:
1776:
414:
such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the
2118:
2275:
2263:
2248:
1678:
1207:
570:
251:
241:
45:
2444:
3246:
2803:
2672:
Feldspar And
Nepheline Syenite. U.S. Geological Survey, Mineral Commodity Summaries, January 2020
2568:
2131:
1794:
1682:
1217:
1203:
1132:
915:
343:
Compositional phase diagram of the different minerals that constitute the feldspar solid solution
208:
1148:
sanitaryware, tableware and tile) and other uses, such as fillers, accounted for the remainder.
3374:
2746:
2516:
2486:
2390:
2226:
2186:
2036:
1992:
1941:
1900:
1873:
1845:
1048:
477:
427:
1285:
1245:
Typical mineralogical and chemical analyses of three commercial grades used in ceramics are:
3313:
2952:
2478:
2123:
1982:
1933:
1784:
1703:
1690:
1116:
919:
703:. It is a mineral associated with hydrothermal alteration of the primary feldspar minerals.
465:
453:
423:
353:
291:
271:
73:
3352:
3201:
2690:
2060:
2018:
1647:
1643:
1543:
1108:
998:
407:
2109:
1978:
1929:
1780:
3209:
3046:
2781:
1027:
551:
442:
179:
2149:
565:
The ratio of alkali feldspar to plagioclase feldspar, together with the proportion of
39:
3368:
3241:
2776:
1937:
1798:
688:
559:
301:
66:
2135:
1119:
are clays and clays are the dominant minerals in the most common sedimentary rocks,
3287:
3273:
3269:
3256:
3107:
2852:
2096:
Le Bas, M. J.; Streckeisen, A. L. (1991). "The IUGS systematics of igneous rocks".
1631:
1104:
in solution, with the variety of ions controlled by the type of feldspar reacting.
1085:
646:
49:
1844:(5th ed.). Alexandria, Virginia: American Geological Institute. p. 232.
2482:
1987:
1962:
3113:
3024:
2881:
2011:
1670:
1666:
911:
856:
664:
555:
461:
457:
311:
2470:
2083:
3261:
3235:
2993:
2987:
1812:
1081:
1077:
787:
738:
673:
626:
594:
590:
488:
188:
2185:(2nd ed.). Cambridge, UK: Cambridge University Press. pp. 139â143.
2127:
1996:
3264:
3214:
3146:
3141:
3098:
3052:
3032:
3028:
2929:
2914:
2909:
2841:
2410:
1674:
1635:
1097:
888:
872:
764:
760:
630:
529:
495:
492:
446:
339:
184:
86:
83:
2764:
3283:
3251:
3230:
3164:
3118:
3093:
3083:
3041:
3003:
2947:
2904:
2876:
2826:
2694:
1611:
1093:
803:
669:
610:
2791:. Vol. 10 (11th ed.). Cambridge University Press. p. 245.
2587:
1789:
1764:
3277:
3204:
3088:
3015:
2964:
2871:
2861:
2348:
2327:
1639:
1290:
1221:
1120:
1112:
719:
677:
533:
498:
449:
434:
281:
134:
89:
2477:, NATO ASI Series, Dordrecht: Springer Netherlands, pp. 595â630,
2360:
2313:
2300:
3196:
3159:
3156:
3152:
3036:
3020:
2919:
1136:
1111:
means that clays are very abundant weathering products. About 40% of
1089:
923:
771:
566:
516:
512:
504:
411:
112:
100:
2681:'Feldspar Facts' A. Sugden. Ceramic Review, Issue 207, May/June 2004
2635:'Industrial Ceramics' F.Singer, S.S.Singer. Chapman & Hall, 1971
2709:"NASA Rover's First Soil Studies Help Fingerprint Martian Minerals"
1057:
refers to materials that contain feldspar. The alternate spelling,
3136:
3103:
3009:
2999:
2958:
2886:
2278:. Feldspar Amethyst Galleries, Inc. Retrieved on February 8, 2008.
2266:. Feldspar Amethyst Galleries, Inc. Retrieved on February 8, 2008.
2251:. Feldspar Amethyst Galleries, Inc. Retrieved on February 8, 2008.
578:. K-feldspar is the final feldspar to crystallize from the magma.
438:
338:
422:(potassium-sodium) feldspars. Feldspars make up about 60% of the
3291:
3225:
3218:
3170:
2969:
2924:
2866:
2835:
Gemmological classifications by E. Ya. Kievlenko (1980), updated
2712:
1662:
1567:
1233:
1124:
2799:
1840:
Neuendorf, K.K.E.; Mehl, J.P. Jr.; Jackson, J.A., eds. (2005).
715:
The barium feldspars are monoclinic and include the following:
2780:
1101:
2387:
Die Namen der Steine. Das
Mineralreich im Spiegel der Sprache
2795:
2086:
Industrial
Minerals Association. Retrieved on July 18, 2007.
1198:: In earth sciences and archaeology, feldspars are used for
386:
2567:
Earle, Steven (September 2015). "5.2 Chemical
Weathering".
362:
1924:. Vol. 3. New York: Elsevier Science. pp. 1â64.
2647:"Visiting Our Past: Feldspar mining and racial tensions"
1896:
Geomorphology: The
Mechanics and Chemistry of Landscapes
1582:
Crystallized white feldspar, with an upright 4 cm
1863:
1861:
1706: â List of minerals with Knowledge (XXG) articles
947:
Diagram showing part of a crankshaft chain of feldspar
2157:
British
Geological Survey: Rock Classification Scheme
691:
is an ammonium feldspar with the chemical formula: NH
395:
380:
377:
359:
1170:
and CaO as stabilizers. As an important source of Al
1069:
lica, unrelated to the obsolete spelling 'felspar'.
383:
371:
365:
3301:
3189:
3127:
3074:
3065:
2978:
2938:
2895:
2850:
2840:
2221:Klein, Cornelis; Hurlbut, Cornelius S. Jr. (1993).
1872:. London: Geological Society of London. p. 2.
1053:, meaning a non-opaque mineral with good cleavage.
914:composition is due to very fine-grained exsolution
356:
328:
320:
310:
300:
290:
280:
270:
260:
250:
240:
227:
217:
207:
199:
194:
178:
168:
72:
62:
57:
32:
1893:Anderson, Robert S.; Anderson, Suzanne P. (2010).
983:Feldspar crystal structure viewed along the b axis
971:Feldspar crystal structure viewed along the a axis
959:Feldspar crystal structure viewed along the c axis
2223:Manual of mineralogy : (after James D. Dana)
663:Potassium and sodium feldspars are not perfectly
2547:Professor's lecture notes (EENS 211, Mineralogy)
672:is a typical texture in alkali feldspar, due to
2389:(2nd ed.), Thun: Ott Verlag, p. 215,
2225:(21st ed.). New York: Wiley. p. 559.
2183:Principles of igneous and metamorphic petrology
1224:) use feldspar to give a mild abrasive action.
763:. The plagioclase series follows (with percent
2150:"Rock Classification Scheme - Vol 1 - Igneous"
1835:
1833:
2811:
2244:
2242:
1870:Rock-forming Minerals (2nd edition) Volume 4A
1685:. This sample is currently on display at the
8:
2372:
2287:
2181:Philpotts, Anthony R.; Ague, Jay J. (2009).
1868:Deer, W.A; Howie, R.A.; Zussman, J. (2001).
1549:found high feldspar content in a Mars rock.
1038:
1031:
1021:
1015:
1008:
1001:
464:. Feldspars are also found in many types of
452:rocks and are also present in many types of
2691:Nasa's Curiosity rover finds 'unusual rock'
2259:
2257:
2078:
2076:
2074:
2072:
2070:
1899:. Cambridge University Press. p. 187.
1598:Feldspar and moonstone, from Sonora, Mexico
476:The feldspar group of minerals consists of
3335:
3071:
2847:
2818:
2804:
2796:
2469:Blum, Alex E. (1994), Parsons, Ian (ed.),
2031:Blatt, Harvey and Tracy, Robert J. (1996)
1247:
1123:. They are also an important component of
1107:The abundance of feldspars in the Earth's
38:
2299:Ralph, Jolyon and Chou, Ida. "Perthite".
2117:
1986:
1788:
922:in the plagioclase series increases from
1710:List of countries by feldspar production
902:
898:
894:
882:
878:
866:
862:
797:
793:
781:
777:
747:
743:
732:
728:
724:
656:
652:
640:
636:
620:
616:
604:
600:
456:. Rock formed almost entirely of calcic
2622:
2620:
2511:Hefferan, Kevin; O'Brien, John (2010).
2361:Celsianâhyalophane series on Mindat.org
2349:Celsianâorthoclase series on Mindat.org
1755:
1614:feldspar crystals with a schorl crystal
1556:
937:
1026:had long been used as the word for "a
29:
2582:
2580:
2536:
2534:
2532:
2515:. Wiley-Blackwell. pp. 336â337.
2464:
2462:
2443:. Oxford Dictionaries. Archived from
7:
2051:"Weathering and Sedimentary Rocks."
1765:"IMAâCNMNC approved mineral symbols"
1216:: Some household cleaners (such as
1047:was influenced by the English word
418:(sodium-calcium) feldspars and the
2707:Brown, Dwayne (October 30, 2012).
2208:The Evolution of the Igneous Rocks
1687:National Museum of Natural History
918:known as Bøggild intergrowth. The
14:
2098:Journal of the Geological Society
926:(2.62) to anorthite (2.72â2.75).
3346:
3334:
2763:
2543:"Weathering & Clay Minerals"
2541:Nelson, Stephen A. (Fall 2008).
2303:. Retrieved on February 8, 2008.
2210:. Canada: Dover. pp. 60â62.
2170:from the original on 2022-10-09.
1731: This article incorporates
1726:
1655:
1619:
1603:
1591:
1575:
1559:
976:
964:
952:
940:
408:aluminium tectosilicate minerals
352:
2948:Yellow, Green, Violet Sapphires
2741:Bonewitz, Ronald Louis (2005).
1747:United States Geological Survey
2645:Neufeld, Rob (4 August 2019).
2612:Feldspar and nepheline syenite
2301:Perthite Profile on mindat.org
2035:Freeman, 2nd ed., pp. 206â210
1938:10.1016/B0-08-043751-6/03016-4
1739:Feldspar and nepheline syenite
759:The plagioclase feldspars are
203:pink, white, gray, brown, blue
16:Group of rock-forming minerals
1:
2614:, USGS 2008 Minerals Yearbook
2475:Feldspars and their Reactions
2012:Metamorphic Rocks Information
1186:, no volatiles and no waste.
1030:easily cleaved into flakes";
406:) is a group of rock-forming
3340:List of gemstones by species
3309:List of individual gemstones
2970:Precious White and Fire Opal
2483:10.1007/978-94-011-1106-5_15
2022:. Retrieved on July 18, 2007
2745:. New York: DK Publishing.
2416:Online Etymology Dictionary
2064:Retrieved on July 18, 2007.
1961:TROLL, V. R. (2002-02-01).
1566:Specimen of rare plumbian (
489:potassium feldspar (K-spar)
3411:
1988:10.1093/petrology/43.2.243
1154:: Feldspar provides both K
1006:, a compound of the words
324:exsolution lamellae common
18:
3332:
3324:List of sapphires by size
2833:
2471:"Feldspars in Weathering"
2441:Oxford English Dictionary
37:
21:Feldspar (disambiguation)
3319:List of emeralds by size
2373:Klein & Hurlbut 1993
2288:Klein & Hurlbut 1993
2249:"The Mineral Orthoclase"
2128:10.1144/gsjgs.148.5.0825
1922:Treatise on Geochemistry
1715:Rainbow lattice sunstone
1673:feldspar). Collected by
1278:
1264:
1250:
1080:of feldspars happens by
410:, also containing other
2788:EncyclopĂŚdia Britannica
2652:Asheville Citizen-Times
576:Bowen's reaction series
569:, is the basis for the
426:and 41% of the Earth's
1769:Mineralogical Magazine
1733:public domain material
1200:potassium-argon dating
1039:
1032:
1022:
1016:
1009:
1002:
344:
2887:Natural marine pearls
2447:on September 26, 2016
2385:Hans LĂźschen (1979),
2276:"Microcline Feldspar"
2009:"Metamorphic Rocks."
1586:crystal perched on it
1542:In October 2012, the
1162:O for fluxing, and Al
755:Plagioclase feldspars
460:feldspar is known as
342:
321:Other characteristics
223:along cleavage planes
52:, southeastern Brazil
3006:, pink, yellow-green
2772:at Wikimedia Commons
2693:. (12 October 2012)
2206:Bowen, N.L. (1956).
1967:Journal of Petrology
1650:", October 17, 2012)
402:; sometimes spelled
46:Jequitinhonha valley
19:For other uses, see
3395:Industrial minerals
3390:Monoclinic minerals
3353:Minerals portal
2925:Precious Black Opal
2549:. Tulane University
2375:, pp. 533â534.
2290:, pp. 532â536.
2264:"Sanidine Feldspar"
2110:1991JGSoc.148..825L
1979:2002JPet...43..243T
1930:2003TrGeo...3....1R
1842:Glossary of Geology
1790:10.1180/mgm.2021.43
1781:2021MinM...85..291W
1763:Warr, L.N. (2021).
1326:Microcline, %
1208:luminescence dating
1078:Chemical weathering
571:QAPF classification
3385:Triclinic minerals
3175:Opaque iridescent
3066:Jewelry-Industrial
3012:yellow, blue, pink
2059:2007-07-03 at the
2017:2007-07-01 at the
1340:Anorthite, %
1279:Producing company
1218:Bar Keepers Friend
1204:argon-argon dating
861:(Ca,Na)Al(Al,Si)Si
792:(Na,Ca)(Al,Si)AlSi
345:
3362:
3361:
3190:Industrial stones
3185:
3184:
3061:
3060:
2768:Media related to
2751:978-0-7566-3342-4
2610:Apodaca, Lori E.
2522:978-1-4443-3460-9
2492:978-94-011-1106-5
2409:Harper, Douglas.
2084:What is Feldspar?
1947:978-0-08-043751-4
1535:
1534:
1241:Commercial grades
1117:sedimentary rocks
997:derives from the
767:in parentheses):
684:Ammonium feldspar
466:sedimentary rocks
428:continental crust
335:
334:
3402:
3351:
3350:
3349:
3338:
3337:
3314:List of diamonds
3072:
2848:
2820:
2813:
2806:
2797:
2792:
2784:
2767:
2729:
2728:
2726:
2724:
2715:. Archived from
2704:
2698:
2688:
2682:
2679:
2673:
2670:
2664:
2663:
2661:
2659:
2642:
2636:
2633:
2627:
2624:
2615:
2608:
2602:
2601:
2599:
2598:
2584:
2575:
2574:
2570:Physical Geology
2564:
2558:
2557:
2555:
2554:
2538:
2527:
2526:
2508:
2502:
2501:
2500:
2499:
2466:
2457:
2456:
2454:
2452:
2433:
2427:
2426:
2424:
2423:
2406:
2400:
2399:
2382:
2376:
2370:
2364:
2358:
2352:
2346:
2340:
2339:
2337:
2335:
2328:"Feldspar Group"
2324:
2318:
2317:
2310:
2304:
2297:
2291:
2285:
2279:
2273:
2267:
2261:
2252:
2246:
2237:
2236:
2218:
2212:
2211:
2203:
2197:
2196:
2178:
2172:
2171:
2169:
2154:
2146:
2140:
2139:
2121:
2093:
2087:
2080:
2065:
2063:
2049:
2043:
2029:
2023:
2021:
2007:
2001:
2000:
1990:
1958:
1952:
1951:
1917:
1911:
1910:
1890:
1884:
1883:
1865:
1856:
1855:
1837:
1828:
1827:
1825:
1823:
1809:
1803:
1802:
1792:
1760:
1750:
1744:
1730:
1729:
1704:List of minerals
1691:Washington, D.C.
1683:Descartes Crater
1659:
1623:
1607:
1595:
1579:
1563:
1538:Extraterrestrial
1354:Quartz , %
1294:
1248:
1042:
1035:
1025:
1019:
1012:
1005:
980:
968:
956:
944:
920:specific gravity
905:
885:
869:
853:
852:
851:
843:
842:
834:
833:
825:
824:
816:
815:
800:
784:
750:
735:
707:Barium feldspars
659:
643:
623:
607:
582:Alkali feldspars
454:metamorphic rock
398:
393:
392:
389:
388:
385:
382:
379:
374:
373:
368:
367:
364:
361:
358:
292:Refractive index
272:Specific gravity
233:
164:
163:
162:
154:
153:
145:
144:
132:
131:
123:
122:
110:
109:
99:
98:
79:
78:(repeating unit)
42:
30:
3410:
3409:
3405:
3404:
3403:
3401:
3400:
3399:
3365:
3364:
3363:
3358:
3347:
3345:
3328:
3297:
3181:
3123:
3067:
3057:
2974:
2934:
2891:
2836:
2829:
2824:
2782:"Felspar"
2775:
2760:
2738:
2736:Further reading
2733:
2732:
2722:
2720:
2719:on June 3, 2016
2706:
2705:
2701:
2689:
2685:
2680:
2676:
2671:
2667:
2657:
2655:
2644:
2643:
2639:
2634:
2630:
2625:
2618:
2609:
2605:
2596:
2594:
2586:
2585:
2578:
2566:
2565:
2561:
2552:
2550:
2540:
2539:
2530:
2523:
2513:Earth Materials
2510:
2509:
2505:
2497:
2495:
2493:
2468:
2467:
2460:
2450:
2448:
2435:
2434:
2430:
2421:
2419:
2408:
2407:
2403:
2397:
2384:
2383:
2379:
2371:
2367:
2359:
2355:
2347:
2343:
2333:
2331:
2326:
2325:
2321:
2314:"Buddingtonite"
2312:
2311:
2307:
2298:
2294:
2286:
2282:
2274:
2270:
2262:
2255:
2247:
2240:
2233:
2220:
2219:
2215:
2205:
2204:
2200:
2193:
2180:
2179:
2175:
2167:
2152:
2148:
2147:
2143:
2119:10.1.1.692.4446
2095:
2094:
2090:
2081:
2068:
2061:Wayback Machine
2052:
2050:
2046:
2030:
2026:
2019:Wayback Machine
2010:
2008:
2004:
1960:
1959:
1955:
1948:
1919:
1918:
1914:
1907:
1892:
1891:
1887:
1880:
1867:
1866:
1859:
1852:
1839:
1838:
1831:
1821:
1819:
1817:Gemology Online
1811:
1810:
1806:
1762:
1761:
1757:
1742:
1736:
1727:
1723:
1700:
1693:
1679:Lunar Highlands
1660:
1651:
1644:Curiosity rover
1624:
1615:
1608:
1599:
1596:
1587:
1580:
1571:
1570:-rich) feldspar
1564:
1555:
1540:
1507:
1489:
1443:
1425:
1421:
1403:
1399:
1381:
1312:Albite, %
1288:
1243:
1230:
1185:
1181:
1177:
1173:
1169:
1165:
1161:
1157:
1145:
1075:
991:
984:
981:
972:
969:
960:
957:
948:
945:
932:
904:
900:
896:
892:
884:
880:
877:(NaSi,CaAl)AlSi
876:
868:
864:
860:
850:
847:
846:
845:
841:
838:
837:
836:
832:
829:
828:
827:
823:
820:
819:
818:
814:
811:
810:
809:
807:
799:
795:
791:
783:
779:
775:
757:
749:
745:
741:
734:
730:
726:
722:
709:
702:
698:
694:
686:
658:
654:
650:
642:
638:
634:
622:
618:
614:
606:
602:
598:
584:
552:Solid solutions
547:
543:
539:
526:
522:
509:
503:
474:
396:
376:
370:
355:
351:
337:
336:
231:
161:
158:
157:
156:
152:
149:
148:
147:
143:
140:
139:
138:
130:
127:
126:
125:
121:
118:
117:
116:
108:
105:
104:
103:
97:
94:
93:
92:
82:
77:
76:
53:
24:
17:
12:
11:
5:
3408:
3406:
3398:
3397:
3392:
3387:
3382:
3380:Tectosilicates
3377:
3367:
3366:
3360:
3359:
3357:
3356:
3333:
3330:
3329:
3327:
3326:
3321:
3316:
3311:
3305:
3303:
3299:
3298:
3296:
3295:
3281:
3267:
3259:
3254:
3249:
3244:
3239:
3233:
3228:
3222:
3212:
3210:Petrified wood
3207:
3199:
3193:
3191:
3187:
3186:
3183:
3182:
3180:
3179:
3173:
3167:
3162:
3149:
3144:
3139:
3133:
3131:
3125:
3124:
3122:
3121:
3116:
3111:
3101:
3096:
3091:
3086:
3080:
3078:
3069:
3063:
3062:
3059:
3058:
3056:
3055:
3049:
3044:
3039:
3018:
3013:
3007:
2997:
2996:, polychromous
2991:
2984:
2982:
2976:
2975:
2973:
2972:
2967:
2962:
2955:
2950:
2944:
2942:
2936:
2935:
2933:
2932:
2927:
2922:
2917:
2912:
2907:
2901:
2899:
2893:
2892:
2890:
2889:
2884:
2879:
2874:
2869:
2864:
2858:
2856:
2845:
2838:
2837:
2834:
2831:
2830:
2825:
2823:
2822:
2815:
2808:
2800:
2794:
2793:
2779:, ed. (1911).
2777:Chisholm, Hugh
2773:
2759:
2758:External links
2756:
2755:
2754:
2737:
2734:
2731:
2730:
2699:
2683:
2674:
2665:
2637:
2628:
2616:
2603:
2592:www.mindat.org
2576:
2559:
2528:
2521:
2503:
2491:
2458:
2428:
2401:
2395:
2377:
2365:
2353:
2341:
2319:
2305:
2292:
2280:
2268:
2253:
2238:
2231:
2213:
2198:
2191:
2173:
2163:: 1â52. 1999.
2141:
2104:(5): 825â833.
2088:
2066:
2044:
2024:
2002:
1973:(2): 243â270.
1953:
1946:
1912:
1905:
1885:
1878:
1857:
1851:978-0922152896
1850:
1829:
1804:
1775:(3): 291â320.
1754:
1753:
1752:
1751:
1722:
1719:
1718:
1717:
1712:
1707:
1699:
1696:
1695:
1694:
1661:
1654:
1652:
1625:
1618:
1616:
1609:
1602:
1600:
1597:
1590:
1588:
1581:
1574:
1572:
1565:
1558:
1554:
1551:
1539:
1536:
1533:
1532:
1529:
1526:
1523:
1519:
1518:
1515:
1512:
1509:
1505:
1501:
1500:
1497:
1494:
1491:
1487:
1483:
1482:
1479:
1476:
1473:
1469:
1468:
1465:
1462:
1459:
1455:
1454:
1451:
1448:
1445:
1441:
1437:
1436:
1433:
1430:
1427:
1423:
1419:
1415:
1414:
1411:
1408:
1405:
1401:
1397:
1393:
1392:
1389:
1386:
1383:
1379:
1375:
1374:
1372:
1370:
1368:
1365:
1364:
1361:
1358:
1355:
1351:
1350:
1347:
1344:
1341:
1337:
1336:
1333:
1330:
1327:
1323:
1322:
1319:
1316:
1313:
1309:
1308:
1306:
1304:
1302:
1299:
1298:
1295:
1283:
1280:
1276:
1275:
1272:
1269:
1266:
1262:
1261:
1258:
1255:
1252:
1242:
1239:
1229:
1226:
1196:Earth sciences
1183:
1179:
1175:
1171:
1167:
1163:
1159:
1155:
1144:
1141:
1074:
1071:
1014:("field") and
990:
987:
986:
985:
982:
975:
973:
970:
963:
961:
958:
951:
949:
946:
939:
931:
928:
907:
906:
886:
870:
854:
848:
839:
830:
821:
812:
801:
785:
756:
753:
752:
751:
736:
708:
705:
700:
696:
692:
685:
682:
661:
660:
644:
624:
608:
583:
580:
549:
548:
545:
541:
537:
527:
524:
520:
510:
507:
501:
478:tectosilicates
473:
470:
333:
332:
330:
326:
325:
322:
318:
317:
314:
308:
307:
304:
298:
297:
294:
288:
287:
284:
278:
277:
274:
268:
267:
264:
258:
257:
254:
248:
247:
244:
238:
237:
234:
225:
224:
221:
215:
214:
211:
205:
204:
201:
197:
196:
195:Identification
192:
191:
182:
180:Crystal system
176:
175:
172:
166:
165:
159:
150:
141:
128:
119:
106:
95:
80:
70:
69:
64:
60:
59:
55:
54:
43:
35:
34:
28:
27:
15:
13:
10:
9:
6:
4:
3:
2:
3407:
3396:
3393:
3391:
3388:
3386:
3383:
3381:
3378:
3376:
3373:
3372:
3370:
3355:
3354:
3343:
3342:
3341:
3331:
3325:
3322:
3320:
3317:
3315:
3312:
3310:
3307:
3306:
3304:
3300:
3293:
3289:
3285:
3282:
3279:
3275:
3271:
3268:
3266:
3263:
3260:
3258:
3255:
3253:
3250:
3248:
3245:
3243:
3240:
3237:
3234:
3232:
3229:
3227:
3223:
3220:
3216:
3213:
3211:
3208:
3206:
3203:
3200:
3198:
3195:
3194:
3192:
3188:
3178:
3174:
3172:
3168:
3166:
3163:
3161:
3158:
3154:
3150:
3148:
3145:
3143:
3140:
3138:
3135:
3134:
3132:
3130:
3126:
3120:
3117:
3115:
3112:
3109:
3105:
3102:
3100:
3097:
3095:
3092:
3090:
3087:
3085:
3082:
3081:
3079:
3077:
3073:
3070:
3064:
3054:
3050:
3048:
3045:
3043:
3040:
3038:
3034:
3030:
3026:
3022:
3019:
3017:
3014:
3011:
3008:
3005:
3001:
2998:
2995:
2992:
2989:
2986:
2985:
2983:
2981:
2977:
2971:
2968:
2966:
2963:
2960:
2956:
2954:
2951:
2949:
2946:
2945:
2943:
2941:
2937:
2931:
2928:
2926:
2923:
2921:
2918:
2916:
2913:
2911:
2908:
2906:
2905:Pink sapphire
2903:
2902:
2900:
2898:
2894:
2888:
2885:
2883:
2880:
2878:
2877:Blue Sapphire
2875:
2873:
2870:
2868:
2865:
2863:
2860:
2859:
2857:
2855:
2854:
2849:
2846:
2843:
2839:
2832:
2828:
2821:
2816:
2814:
2809:
2807:
2802:
2801:
2798:
2790:
2789:
2783:
2778:
2774:
2771:
2766:
2762:
2761:
2757:
2752:
2748:
2744:
2740:
2739:
2735:
2718:
2714:
2710:
2703:
2700:
2696:
2692:
2687:
2684:
2678:
2675:
2669:
2666:
2654:
2653:
2648:
2641:
2638:
2632:
2629:
2623:
2621:
2617:
2613:
2607:
2604:
2593:
2589:
2583:
2581:
2577:
2572:
2571:
2563:
2560:
2548:
2544:
2537:
2535:
2533:
2529:
2524:
2518:
2514:
2507:
2504:
2494:
2488:
2484:
2480:
2476:
2472:
2465:
2463:
2459:
2446:
2442:
2438:
2432:
2429:
2418:
2417:
2412:
2405:
2402:
2398:
2396:3-7225-6265-1
2392:
2388:
2381:
2378:
2374:
2369:
2366:
2362:
2357:
2354:
2350:
2345:
2342:
2329:
2323:
2320:
2315:
2309:
2306:
2302:
2296:
2293:
2289:
2284:
2281:
2277:
2272:
2269:
2265:
2260:
2258:
2254:
2250:
2245:
2243:
2239:
2234:
2228:
2224:
2217:
2214:
2209:
2202:
2199:
2194:
2192:9780521880060
2188:
2184:
2177:
2174:
2166:
2162:
2158:
2151:
2145:
2142:
2137:
2133:
2129:
2125:
2120:
2115:
2111:
2107:
2103:
2099:
2092:
2089:
2085:
2079:
2077:
2075:
2073:
2071:
2067:
2062:
2058:
2055:
2048:
2045:
2042:
2041:0-7167-2438-3
2038:
2034:
2028:
2025:
2020:
2016:
2013:
2006:
2003:
1998:
1994:
1989:
1984:
1980:
1976:
1972:
1968:
1964:
1957:
1954:
1949:
1943:
1939:
1935:
1931:
1927:
1923:
1916:
1913:
1908:
1906:9781139788700
1902:
1898:
1897:
1889:
1886:
1881:
1879:1-86239-081-9
1875:
1871:
1864:
1862:
1858:
1853:
1847:
1843:
1836:
1834:
1830:
1818:
1814:
1808:
1805:
1800:
1796:
1791:
1786:
1782:
1778:
1774:
1770:
1766:
1759:
1756:
1748:
1741:
1740:
1734:
1725:
1724:
1720:
1716:
1713:
1711:
1708:
1705:
1702:
1701:
1697:
1692:
1688:
1684:
1680:
1676:
1672:
1668:
1664:
1658:
1653:
1649:
1645:
1641:
1637:
1633:
1629:
1622:
1617:
1613:
1610:A cluster of
1606:
1601:
1594:
1589:
1585:
1578:
1573:
1569:
1562:
1557:
1552:
1550:
1548:
1546:
1537:
1530:
1527:
1524:
1521:
1520:
1516:
1513:
1510:
1503:
1502:
1498:
1495:
1492:
1485:
1484:
1480:
1477:
1474:
1471:
1470:
1466:
1463:
1460:
1457:
1456:
1452:
1449:
1446:
1439:
1438:
1434:
1431:
1428:
1417:
1416:
1412:
1409:
1406:
1395:
1394:
1390:
1387:
1384:
1377:
1376:
1373:
1371:
1369:
1367:
1366:
1362:
1359:
1356:
1353:
1352:
1348:
1345:
1342:
1339:
1338:
1334:
1331:
1328:
1325:
1324:
1320:
1317:
1314:
1311:
1310:
1307:
1305:
1303:
1301:
1300:
1296:
1292:
1287:
1284:
1281:
1277:
1273:
1270:
1267:
1263:
1259:
1256:
1253:
1249:
1246:
1240:
1238:
1235:
1227:
1225:
1223:
1219:
1215:
1211:
1209:
1205:
1201:
1197:
1193:
1191:
1187:
1153:
1149:
1142:
1140:
1138:
1134:
1128:
1126:
1122:
1118:
1114:
1110:
1105:
1103:
1099:
1095:
1091:
1087:
1086:clay minerals
1084:and produces
1083:
1079:
1072:
1070:
1068:
1064:
1060:
1056:
1052:
1051:
1046:
1041:
1034:
1029:
1024:
1018:
1013:
1011:
1004:
1000:
996:
988:
979:
974:
967:
962:
955:
950:
943:
938:
936:
929:
927:
925:
921:
917:
913:
890:
887:
874:
871:
858:
855:
805:
802:
789:
786:
773:
770:
769:
768:
766:
762:
754:
742:(K,Ba)(Al,Si)
740:
737:
721:
718:
717:
716:
713:
706:
704:
690:
689:Buddingtonite
683:
681:
679:
675:
671:
666:
648:
645:
632:
628:
625:
613:(monoclinic)
612:
609:
596:
592:
589:
588:
587:
581:
579:
577:
572:
568:
563:
561:
560:immiscibility
557:
553:
535:
531:
528:
518:
514:
511:
506:
500:
497:
494:
490:
487:
486:
485:
483:
479:
471:
469:
467:
463:
459:
455:
451:
448:
444:
440:
436:
431:
429:
425:
424:Earth's crust
421:
417:
413:
409:
405:
401:
400:
391:
349:
341:
331:
327:
323:
319:
315:
313:
309:
305:
303:
302:Birefringence
299:
295:
293:
289:
285:
283:
279:
275:
273:
269:
265:
263:
259:
255:
253:
249:
245:
243:
239:
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230:
226:
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220:
216:
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210:
206:
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198:
193:
190:
186:
183:
181:
177:
173:
171:
167:
136:
114:
102:
91:
88:
85:
81:
75:
71:
68:
67:Tectosilicate
65:
61:
56:
51:
47:
41:
36:
31:
26:
22:
3344:
3288:Pyrophyllite
3257:Serpentinite
3238:(green mica)
3176:
3128:
3108:Baltic amber
3075:
2979:
2939:
2896:
2851:
2786:
2743:Rock and Gem
2742:
2721:. Retrieved
2717:the original
2702:
2686:
2677:
2668:
2656:. Retrieved
2650:
2640:
2631:
2606:
2595:. Retrieved
2591:
2569:
2562:
2551:. Retrieved
2546:
2512:
2506:
2496:, retrieved
2474:
2449:. Retrieved
2445:the original
2440:
2431:
2420:. Retrieved
2414:
2404:
2386:
2380:
2368:
2356:
2344:
2332:. Retrieved
2330:. mindat.org
2322:
2308:
2295:
2283:
2271:
2222:
2216:
2207:
2201:
2182:
2176:
2160:
2156:
2144:
2101:
2097:
2091:
2047:
2032:
2027:
2005:
1970:
1966:
1956:
1921:
1915:
1895:
1888:
1869:
1841:
1820:. Retrieved
1816:
1807:
1772:
1768:
1758:
1738:
1632:Martian soil
1544:
1541:
1522:LOI, %
1472:MgO, %
1458:CaO, %
1251:Product name
1244:
1231:
1213:
1212:
1195:
1194:
1189:
1188:
1151:
1150:
1146:
1143:Applications
1129:
1106:
1088:, including
1076:
1066:
1062:
1058:
1054:
1049:
1044:
1007:
994:
992:
933:
908:
891:(90 to 100)
826: â CaAl
758:
714:
710:
687:
662:
649:(triclinic)
647:anorthoclase
585:
564:
550:
475:
472:Compositions
432:
419:
415:
403:
347:
346:
213:two or three
50:Minas Gerais
25:
3270:Ophicalcite
3151:Colorless,
3114:Chrysoprase
3025:Spessartine
2990:â Verdelite
2882:Alexandrite
2723:October 31,
2573:. BCcampus.
1671:plagioclase
1667:anorthosite
1634:âfeldspar,
1289: [
1133:transported
1055:Feldspathic
1020:("flake").
912:labradorite
875:(70 to 90)
859:(50 to 70)
857:labradorite
806:(30 to 50)
790:(10 to 30)
556:plagioclase
462:anorthosite
458:plagioclase
435:crystallize
430:by weight.
416:plagioclase
312:Pleochroism
306:first order
296:1.518â1.526
262:Diaphaneity
3369:Categories
3274:Serpentine
3262:Aventurine
3236:Listwanite
3027:(malaya),
2994:Indicolite
2988:Tourmaline
2961:(Imperial)
2953:Aquamarine
2597:2020-11-18
2553:2008-11-13
2498:2020-11-18
2451:13 January
2422:2008-02-08
2411:"feldspar"
2232:047157452X
2082:Feldspar.
2033:Petrology,
1822:8 November
1813:"Feldspar"
1721:References
1642:revealed (
1628:X-ray view
1584:aquamarine
1508:O, %
1490:O, %
1282:North Cape
1257:Forshammar
1254:Norfloat K
1228:Production
1082:hydrolysis
1073:Weathering
1065:dspar and
788:oligoclase
774:(0 to 10)
739:hyalophane
674:exsolution
651:(Na,K)AlSi
627:microcline
615:(K,Na)AlSi
595:monoclinic
591:orthoclase
532:endmember
515:endmember
491:endmember
482:endmembers
433:Feldspars
329:References
229:Mohs scale
189:monoclinic
170:IMA symbol
3265:quartzite
3217:(Porouse
3215:Cacholong
3177:feldspars
3147:Rhodonite
3142:Amazonite
3129:2nd order
3099:Malachite
3076:1st order
3053:Turquoise
3033:Almandine
3029:Rhodolite
2980:4th order
2940:3rd order
2930:Tanzanite
2915:Tsavorite
2910:Demantoid
2897:2nd order
2853:1st order
2827:Gemstones
2114:CiteSeerX
1997:1460-2415
1799:235729616
1677:from the
1675:Apollo 16
1636:pyroxenes
1545:Curiosity
1444:, %
1426:, %
1404:, %
1382:, %
1214:Minor use
1098:kaolinite
993:The name
989:Etymology
930:Structure
889:anorthite
873:bytownite
765:anorthite
761:triclinic
631:triclinic
530:anorthite
447:extrusive
443:intrusive
276:2.55â2.76
185:Triclinic
3375:Feldspar
3284:Pagodite
3252:Fluorite
3247:Selenite
3231:Obsidian
3165:Hematite
3119:Charoite
3094:Nephrite
3084:Lazurite
3042:Amethyst
3004:Heliodor
2770:Feldspar
2695:BBC News
2658:4 August
2588:"Arkose"
2165:Archived
2136:28548230
2057:Archived
2054:Geology.
2015:Archived
1698:See also
1669:#60025 (
1665:ferrous
1648:Rocknest
1612:euhedral
1297:Sibelco
1274:Finland
1265:Country
1190:Ceramics
1158:O and Na
1121:mudrocks
1113:minerals
1094:smectite
1033:Feldspat
1003:Feldspat
995:feldspar
916:lamellae
804:andesine
678:granites
670:Perthite
665:miscible
611:sanidine
441:as both
348:Feldspar
246:Vitreous
232:hardness
219:Fracture
209:Cleavage
133: â
111: â
63:Category
33:Feldspar
3302:Related
3278:Calcite
3224:Marble
3205:granite
3202:Graphic
3169:Common
3089:Jadeite
3047:Citrine
3021:Garnets
3016:Peridot
2965:Elbaite
2957:Orange
2872:Emerald
2862:Diamond
2842:Jewelry
2106:Bibcode
1975:Bibcode
1926:Bibcode
1777:Bibcode
1640:olivine
1286:Sibelco
1260:FFF K6
1222:Bon Ami
1137:arkoses
1059:felspar
720:celsian
450:igneous
412:cations
404:felspar
282:Density
236:6.0â6.5
74:Formula
58:General
3197:Jasper
3160:quartz
3068:stones
3037:Pyrope
2920:Spinel
2844:stones
2749:
2519:
2489:
2437:"spar"
2393:
2334:4 July
2229:
2189:
2134:
2116:
2039:
1995:
1944:
1903:
1876:
1848:
1797:
1626:First
1553:Images
1271:Sweden
1268:Norway
1096:, and
1090:illite
999:German
924:albite
808:NaAlSi
776:NaAlSi
772:albite
567:quartz
513:albite
420:alkali
397:FEL(D)
266:opaque
252:Streak
242:Luster
3153:smoky
3137:Agate
3104:Amber
3051:Blue
3010:Topaz
3000:Beryl
2959:topaz
2168:(PDF)
2153:(PDF)
2132:S2CID
1795:S2CID
1743:(PDF)
1735:from
1681:near
1663:Lunar
1547:rover
1481:0.01
1467:0.70
1453:0.01
1435:0.11
1413:18.3
1391:67.9
1293:]
1152:Glass
1125:soils
1109:crust
1045:-spar
635:KAlSi
599:KAlSi
439:magma
437:from
399:-spar
256:white
200:Color
3292:Talc
3226:onyx
3219:opal
3171:opal
3157:pink
3155:and
2867:Ruby
2747:ISBN
2725:2012
2713:NASA
2660:2019
2517:ISBN
2487:ISBN
2453:2018
2391:ISBN
2336:2021
2227:ISBN
2187:ISBN
2037:ISBN
1993:ISSN
1942:ISBN
1901:ISBN
1874:ISBN
1846:ISBN
1824:2012
1646:at "
1568:lead
1531:0.2
1517:5.5
1499:6.4
1493:11.8
1478:0.10
1464:0.30
1461:0.40
1450:0.02
1432:0.15
1429:0.07
1410:14.1
1407:18.6
1388:75.7
1385:65.9
1234:USGS
1232:The
1220:and
1206:and
1102:ions
1050:spar
1040:Spat
1028:rock
1023:Spat
1017:Spat
1010:Feld
893:CaAl
723:BaAl
695:AlSi
519:AlSi
445:and
316:none
286:2.56
115:AlSi
3242:Jet
2479:doi
2124:doi
2102:148
1983:doi
1934:doi
1785:doi
1689:in
1630:of
1528:0.5
1525:0.2
1514:5.0
1511:2.9
1496:3.8
1440:TiO
1378:SiO
1335:37
1321:41
1115:in
1063:fel
1043:to
387:ÉËr
187:or
174:Fsp
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3035:,
3031:,
3023:â
3002:â
2785:.
2711:.
2649:.
2619:^
2590:.
2579:^
2545:.
2531:^
2485:,
2473:,
2461:^
2439:.
2413:.
2256:^
2241:^
2159:.
2155:.
2130:.
2122:.
2112:.
2100:.
2069:^
1991:.
1981:.
1971:43
1969:.
1965:.
1940:.
1932:.
1860:^
1832:^
1815:.
1793:.
1783:.
1773:85
1771:.
1767:.
1745:.
1638:,
1504:Na
1418:Fe
1396:Al
1363:8
1360:33
1349:4
1332:23
1329:71
1318:40
1315:23
1291:nl
1210:.
1202:,
1139:.
1092:,
1067:si
897:Si
835:Si
727:Si
633:)
597:)
540:Si
536:Al
534:Ca
517:Na
499:Si
496:Al
484::
468:.
146:Si
137:Al
135:Ca
113:Na
90:Si
87:Al
48:,
3294:)
3290:/
3286:(
3280:)
3276:/
3272:(
3221:)
3110:)
3106:(
2819:e
2812:t
2805:v
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2727:.
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2662:.
2600:.
2556:.
2525:.
2481::
2455:.
2425:.
2363:.
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2338:.
2316:.
2235:.
2195:.
2161:1
2138:.
2126::
2108::
1999:.
1985::
1977::
1950:.
1936::
1928::
1909:.
1882:.
1854:.
1826:.
1801:.
1787::
1779::
1749:.
1506:2
1488:2
1486:K
1475:-
1447:-
1442:2
1424:3
1422:O
1420:2
1402:3
1400:O
1398:2
1380:2
1357:3
1346:-
1343:3
1184:3
1182:O
1180:2
1176:3
1174:O
1172:2
1168:3
1166:O
1164:2
1160:2
1156:2
903:8
901:O
899:2
895:2
883:8
881:O
879:2
867:8
865:O
863:2
849:8
844:O
840:2
831:2
822:8
817:O
813:3
798:8
796:O
794:2
782:8
780:O
778:3
748:8
746:O
744:4
733:8
731:O
729:2
725:2
701:8
699:O
697:3
693:4
657:8
655:O
653:3
641:8
639:O
637:3
629:(
621:8
619:O
617:3
605:8
603:O
601:3
593:(
546:8
544:O
542:2
538:2
525:8
523:O
521:3
508:8
505:O
502:3
493:K
390:/
384:p
381:s
378:Ë
375:)
372:d
369:(
366:l
363:É
360:f
357:Ë
354:/
350:(
160:8
155:O
151:2
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124:O
120:3
107:8
101:O
96:3
84:K
23:.
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