Sapphirine Value, Price, and Jewelry Information
An overview on Sapphirine Jewelry and Gemstones. Covers details and essential information on the physical properties and characteristics of Sapphirine gems.
Sapphirine Value
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Sapphirine Information
| Data | Value |
| Name | Sapphirine |
| Crystallography | Monoclinic or triclinc; crystals tabular; usually granular or as disseminated grains. |
| Colors | Pale blue, bluish gray, greenish gray, green; depth of blue color varies with Fe. Also, (rarely) purplish pink. |
| Luster | Vitreous. |
| Fracture | Uneven to subconchoidal. |
| Hardness | 7.5. |
| Specific Gravity | 3.4-3.5. |
| Birefringence | 0.006. |
| Cleavage | Indistinct. |
| Stone Sizes | Facetable sapphirine is exceedingly rare, even though the material occurs in transparent grains. GIA noted a very unusual purplish-pink stone of 1.54 cts, oval, with included mica “book” (phlogopite), from Sri Lanka; R.l. =1.701—1.707; β= 1.705; birefringence = 0.006; S.G.: 3.51. The refractive indices of sapphirine are close to idocrase, but the former is biaxial. Other such gems exist but have been misidentified. |
| Luminescence | None reported. |
| Spectral | Not diagnostic. |
| Formula | Mg3,5Al9Si4,5O20 (+Fe). Complex substitution of Mg/Al/Si with charge balancing. Two polytypes: Sapphirine-2M = (Mg,Al)8(Al,Si)6O20; monoclinic. Sapphirine-Te=(Mg,Al )8(Al,Si)6O20; triclinic. |
| Pleochroism | Distinct: X = pinkish buff; yellowish; pale smoky brown; colorless: Y=sky blue: sapphire blue: greenish blue; Z=dark sky blue; sapphire blue. |
Optics: a =1.714-1.716; β= 1.719-1.721; γ= 1.720-1.723.
Biaxial (—).
Occurrence: In mineral veins or cavities in eruptive igneous rocks.
Milford, Utah; Keweenaw Peninsula, Michigan; Lake Superior, Minnesota.
Canada; Scotland; England: Sweden; Czechoslovakia;
Japan; South Africa; Greenland; Madagascar: Italy: Sri Lanka.
Name: In allusion to the (sapphire blue) color.
