Color Natural Apatite
Natural Sphene: More Fire Than Diamond
In the gemstone world we have a number of technical terms we use to describe the luster of a gemstone. These terms include metallic, adamantine, pearly, silky, vitreous, resinous, and waxy. The term adamantine means ‘like diamond’ and is used to refer to gemstones which have especially high brilliance and intensive dispersion or fire.
There are very few gemstones that have a luster that deserves to be called adamantine. Diamond is one, of course; the rare demantoid garnet is another. But one of the members of this exclusive group is a gem that few people have heard of, and even fewer have seen: sphene.
Sphene is a calcium titanium silicate that is also known by its mineralogical name, titanite. The name sphene comes from the fact that its crystals are typically sphenoid (from the Greek sphenos meaning wedge). The name titanite comes, not surprisingly, from its titanium content.
Sphene occurs as translucent to transparent, reddish brown, gray, yellow, green, or red monoclinic crystals. Sphene has an unusually high refractive index (1.843-2.110), higher than zircon, ruby and sapphire. But it is sphene’s dispersion or fire which is truly exceptional, exceeding even that of diamond.
When you hold a gemstone and turn it in the light, some gems will display flashes of color, which is the result of the dispersion of white light into the colors of the spectrum. Dispersion occurs when different wavelengths of light are refracted by a different amount by the refracting medium. Diamond is famed for this quality, but sphene actually has a higher dispersion value than diamond. This is why high quality sphene usually looks multicolored in photographs.
In addition to its exceptional fire, sphene is itself strongly pleochroic, meaning it displays more than one color. Sphene typically displays least three colors (colorless, greenish-yellow, reddish) when looked at from different angles. Sphene is usually found with some inclusions and the rare clean pieces are highly sought after.
Sphene has traditionally been rare and sought after mainly by collectors. Recently the supply has improved with new material from Sri Lanka and Madagascar, and sphene is now being used for jewelry. However, sphene is diamond-like only in some respects. It is a fairly soft stone — 5 to 5.5 on the Mohs hardness scale — about the same hardness as apatite, chrome diopside, turquoise and lapis lazuli. So sphene is not suitable as a ring stone for everyday wear. But it makes outstanding pendants and earrings.
About the Author
GemSelect is a leading online dealer in fine gemstones, including sphene, sapphire, spinel, tourmaline, peridot, topaz and zircon. Sphene Photos
Apatite – 29.00 ct.
|
|
2.56 Ct. 4 Pcs. Natural Paraiba Color Apatite Unheated $9.99 |
|
|
0.87 ct Charming Oval Cut Resplendent Unheated Natural Apatite Neon Blue Color $9.99 |
|
|
0.63 Ct. Heart Neon Blue Natural Paraiba Color Apatite Tanzania $1.29 |
|
|
1.13 Ct. Trilliant Natural Gem Paraiba Color Apatite $4.99 |
|
|
0.86 Ct. Oval Shape Natural Gem Paraiba Color Apatite $0.99 |
|
|
2.49 Ct. Oval Shape Natural Paraiba Color Apatite Gem $0.99 |
|
|
PARAIBA COLOR AAA+ 1.79CT.NATURAL GREEN APATITE OVAL AFRICA UNHEATED / GN21864 $7.00 |
|
|
3.89Cts Lovely Fine Quality Luster Color Rich Blue Natural Twin Apatite *DWE19 $9.99 |
|
|
0.89 Ct. Oval Natural Paraiba Color Apatite Unheated $0.99 |
|
|
RARE COLOR NEW MINE NATURAL OVAL RICH OLIVE GREEN TANZANIA APATITE 1.72 CT.LIMIT $29.99 |
|
|
0.90 Ct. 6.5 Mm. Round Natural Paraiba Color Apatite Tanzania $0.99 |
|
|
1.20 Ct. Glistening Natural Paraiba Color Apatite Gem $0.99 |
|
|
1.07 Ct. Oval Natural Paraiba Color Apatite Unheated $0.99 |
|
|
1.00 CTS GREENISH BLUE PARAIBA COLOR! NATURAL APATITE $9.99 |
|
|
2.26Cts Dazzling Quality Top Luster Color Rich Blue Natural Apatite *DTH18 $9.99 |
|
|
1.47 CT GORGEOUS BRIOLETTE NATURAL PARAIBA COLOR APATITE $12.99 |
|
|
1.69 CT DAZZLING BRIOLETTE CUT NATURAL PARAIBA COLOR APATITE $12.99 |
|
|
1.73 CT WONDERFUL BRIOLETTE CUT NATURAL PARAIBA COLOR APATITE $12.99 |
|
|
1.77 CT BEAUTIFUL BRIOLETTE CUT NATURAL PARAIBA COLOR APATITE $12.99 |
|
|
15.00ct 100% NATURAL APATITE ROUGH NEON BLUE PARAIBA COLOR UNTREATED GUARANTEE $96.00 |
|
|
19.25ct 100% NATURAL APATITE ROUGH NEON BLUE PARAIBA COLOR UNTREATED GUARANTEE $96.00 |
|
|
22.35ct 100% NATURAL APATITE ROUGH NEON BLUE PARAIBA COLOR UNTREATED GUARANTEE $72.00 |
|
|
22.50ct 100% NATURAL APATITE ROUGH NEON BLUE PARAIBA COLOR UNTREATED GUARANTEE $120.00 |
|
|
23.20ct 100% NATURAL APATITE ROUGH NEON BLUE PARAIBA COLOR UNTREATED GUARANTEE $64.00 |
|
|
2.83 Ct. 4 Pcs. Natural Paraiba Color Apatite Unheated $10.10 |
|
|
1.03 Ct. Oval Shape Natural Paraiba Color Apatite Gem $0.99 |
|
|
1.58 Ct. 4 Pcs. Natural Paraiba Color Apatite Unheated $7.99 |
|
|
0.95 Ct. Round Natural Paraiba Color Apatite Unheated $7.99 |
|
|
1.42 Ct. Octagon Shape Natural Paraiba Color Apatite $9.99 |
|
|
0.89 ct Fantastic Round Cut Shimmering Unheated Natural Apatite Neon Blue Color $9.99 |
|
|
0.80 Ct. Oval Shape Natural Paraiba Color Apatite Gem $0.99 |
|
|
2.50 Ct. 4 Pcs. Oval Natural Paraiba Color Apatite Unheated $0.99 |
|
|
Unheated 0.70 Ct. Oval Natural Paraiba Color Apatite $0.99 |
|
|
0.82 Ct. Oval Shape Natural Paraiba Color Apatite Gem $0.99 |
|
|
2.26Cts Amazing Fine Quality Luster Color Rich Blue Natural Apatite *DFR19 $9.99 |
|
|
7.30cts-ULTRA RARE AAA LUSTER AND COLOR CANARY YELLOW NATURAL APATITE $139.99 |
|
|
48.30 Ct. Natural Paraiba Color Apatite Beads 10 Inch. Tanzania $133.64 |
|
|
50.40 Ct. 5.6 x 3 Mm. Natural Paraiba Color Apatite Beads Long 10 Inch $139.08 |
|
|
57.90 Ct. 5.4 x 3.4 Mm. Natural Paraiba Color Apatite Beads Long 10 Inch $168.72 |
|
|
64.45 Ct. 4.6 x 3.7 Mm. Natural Paraiba Color Apatite Beads Long 10 Inch $175.32 |
|
|
49.90 Ct. Natural Paraiba Color Apatite Beads Long 10 Inch 5.7 x 3.1 Mm. $146.64 |
|
|
66.10 Ct. Natural Paraiba Color Apatite Bead Length 10 Inch 5.7 x 3.7 Mm. $191.32 |
|
|
58.85 Ct. 5.6 x 3.4 Mm. Natural Paraiba Color Apatite Beads Long 10 Inch $171.31 |
|
|
79.65 Ct. 6 x 3.7 Mm. Natural Paraiba Color Apatite Beads Long 10 Inch $228.72 |
|
|
PARAIBA COLOR! 1.22CT.NATURAL APATITE OVAL AFRICA UNHEATED / GN22441 $0.99 |
|
|
1.12 Ct. Oval Natural Paraiba Color Apatite Tanzania $0.99 |
|
|
2.59 Ct. 4 Pcs. Oval Natural Paraiba Color Apatite Gems $7.99 |
|
|
0.91 Ct. Oval Natural Paraiba Color Apatite Unheated $3.99 |
|
|
0.91 Ct. Oval Shape Natural Paraiba Color Apatite Gem $0.99 |
|
|
0.92 Ct. Oval Natural Paraiba Color Apatite Tanzania $0.99 |
