Difference between revisions of "Titanite"
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[[File:pt20729titanite.jpg|thumb|Titanite]] | [[File:pt20729titanite.jpg|thumb|Titanite]] | ||
== Description == | == Description == | ||
| − | + | [[File:sphene_corrected2.jpg|thumb|Sphene crystals]] | |
Small yellow, gray, green or brown crystals occasionally used as [[gemstone|gemstones]]. Titanite, or sphene, is composed of calcium titanium silicate and is often associated with [[granite|granite]]. Deposits have been found in Canada (Ontario), Mexico, Austria (Tirol), Italy (Trentino), Norway, Switzerland, Madagascar, and the U. S. (New York, Montana, California). Sphene has good luster and fire but is too soft for general wear. | Small yellow, gray, green or brown crystals occasionally used as [[gemstone|gemstones]]. Titanite, or sphene, is composed of calcium titanium silicate and is often associated with [[granite|granite]]. Deposits have been found in Canada (Ontario), Mexico, Austria (Tirol), Italy (Trentino), Norway, Switzerland, Madagascar, and the U. S. (New York, Montana, California). Sphene has good luster and fire but is too soft for general wear. | ||
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* Brittle, wedge-shaped monoclinic crystals | * Brittle, wedge-shaped monoclinic crystals | ||
* Good cleavage in one direction | * Good cleavage in one direction | ||
| − | * Fracture = conchoidal | + | * Luster = vitreous to adamantine |
| + | * Fracture = conchoidal to splintery | ||
* Streak = white | * Streak = white | ||
| − | |||
* Fluorescence = none | * Fluorescence = none | ||
| + | * Pleochroism = moderate to strong | ||
{| class="wikitable" | {| class="wikitable" | ||
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! scope="row"| Refractive Index | ! scope="row"| Refractive Index | ||
| 1.885-1.990; 1.915-2.050 | | 1.885-1.990; 1.915-2.050 | ||
| + | |- | ||
| + | ! scope="row"| Birefringence | ||
| + | | 0.100 - 0.135 (visible doubling) | ||
|} | |} | ||
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==Resources and Citations== | ==Resources and Citations== | ||
| − | + | * Gem Identification Lab Manual, Gemological Institute of America, 2016. | |
* Mineralogy Database: [http://www.webmineral.com/data/Titanite.shtml Titanite] | * Mineralogy Database: [http://www.webmineral.com/data/Titanite.shtml Titanite] | ||
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* ''Encyclopedia Britannica'', http://www.britannica.com Comment: "sphene" [Accessed December 4, 2001] | * ''Encyclopedia Britannica'', http://www.britannica.com Comment: "sphene" [Accessed December 4, 2001] | ||
| − | |||
* C.W.Chesterman, K.E.Lowe, ''Audubon Society Field Guide to North American Rocks and Minerals'', Alfred A. Knopf, New York, 1979 | * C.W.Chesterman, K.E.Lowe, ''Audubon Society Field Guide to North American Rocks and Minerals'', Alfred A. Knopf, New York, 1979 | ||
| − | + | * Wikipedia: [https://en.wikipedia.org/wiki/Titanite Titanite] (Accessed Sept. 17, 2005 and Dec 2022) | |
| − | * Wikipedia: | ||
| − | |||
* ''Van Nostrand's Scientific Encyclopedia'', Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976 | * ''Van Nostrand's Scientific Encyclopedia'', Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976 | ||
| − | |||
* Random House, ''Webster's Encyclopedic Unabridged Dictionary of the English Language'', Grammercy Book, New York, 1997 | * Random House, ''Webster's Encyclopedic Unabridged Dictionary of the English Language'', Grammercy Book, New York, 1997 | ||
| − | |||
* ''The American Heritage Dictionary'' or ''Encarta'', via Microsoft Bookshelf 98, Microsoft Corp., 1998 | * ''The American Heritage Dictionary'' or ''Encarta'', via Microsoft Bookshelf 98, Microsoft Corp., 1998 | ||
Revision as of 15:23, 19 December 2022
Description
Small yellow, gray, green or brown crystals occasionally used as gemstones. Titanite, or sphene, is composed of calcium titanium silicate and is often associated with Granite. Deposits have been found in Canada (Ontario), Mexico, Austria (Tirol), Italy (Trentino), Norway, Switzerland, Madagascar, and the U. S. (New York, Montana, California). Sphene has good luster and fire but is too soft for general wear.
Synonyms and Related Terms
sphene; Titanit (Deut.); Sphen (Deut.); titanita (Esp.); titanite (Fr.); tytanit (Pol.); titanite, esfena (Port.); titaniet (Ned.)
Physical and Chemical Properties
- Brittle, wedge-shaped monoclinic crystals
- Good cleavage in one direction
- Luster = vitreous to adamantine
- Fracture = conchoidal to splintery
- Streak = white
- Fluorescence = none
- Pleochroism = moderate to strong
| Composition | CaTiSiO5 |
|---|---|
| Mohs Hardness | 5.0 - 5.5 |
| Density | 3.4-3.6 g/ml |
| Refractive Index | 1.885-1.990; 1.915-2.050 |
| Birefringence | 0.100 - 0.135 (visible doubling) |
Comparisons
Natural and Simulated Diamonds
Resources and Citations
- Gem Identification Lab Manual, Gemological Institute of America, 2016.
- Mineralogy Database: Titanite
- Encyclopedia Britannica, http://www.britannica.com Comment: "sphene" [Accessed December 4, 2001]
- C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
- Wikipedia: Titanite (Accessed Sept. 17, 2005 and Dec 2022)
- Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998