Tektites pertama kali ditemukan pada tahun 1787 di Cekoslowakia (daerah Moravia) dekat Sungai Moldau, sehingga di beri nama moldavite. Diketahui bahwa tektites berasal dari akibat dari aktivitas
eksplosif batuan luar angkasa ke permukaan
bumi. Tetapi ada juga Ilmuwan yang berpendapat bahwa tektites berasal dari bumi / darat. Masalah ini masih diperdebatkan.
Sedangkan Billitonite sendiri adalah batu tektite yang berasal dari pulau Belitung, Sumatra, Indonesia. Masuk ke dalam Varietas Tektite. Ciri-ciri dari Billitonite adalah batu hitam pekat (opaque 95%). Jika di sorot dengan sinar yang kuat, misal di daerah tepinya akan terlihat sedikit transparansi berwana brown/coklat. Bentuk dari batuan dari alam ini sangat khas dan mudah dikenali.
Tektite Information
| Data | Value |
| Name | Tektite |
| Varieties | Australite, Bikolite, Billitonite, Darwin Glass, Moldavite |
| Crystallography | Amorphous-a glass. |
| Colors | Black, green, greenish brown, brown in moldavites; other tektites black, colorless to brown; usually opaque. |
| Luster | Vitreous. |
| Hardness | 5.5-6.5. |
| Density | 2.21-2.96 [see table). |
| Cleavage | None. Fracture corichoidal. Brittle. |
| Stone Sizes | Faceted gems are usually cut from moldavites because the color of these tektites is lighter than most others. The color is a bottle green resembling diopside, and gems up to about 25 carats have been cut, although very large moldavites have been found. Various other tektites from the United States have been cut as curiosities, mostly small. The refractive index of a tektite seems to vary (positively) with iron content. |
| Luminescence | None in UV. Yellow-green in X-rays. |
| Spectral | Not diagnostic: Moldavites may show two vague bands in the blue and orange. |
| Formula | Silica (75%) + Al, Fe, Ca, Na, K, Mg, Ti, Mn. |
| Inklusi: Sering melihat banyak gelembung bulat atau berbentuk torpedo, juga berputar-putar striae yang tidak seperti yang terlihat dalam pasta (kaca yang digunakan untuk meniru batu permata). | |
 |
| Billitonite, Origin Pulau Bangka Belitung |
Occurrence: Tektites occur worldwide in fields in which the glass bits are literally strewn over the ground, covering a very wide area (see table).
Name
|
Locality
|
Density
|
Refractive Index
|
Color
|
|
| Moldavite* |
Czechoslovakia
|
2.27-3.40
|
1.48-1.54
|
bottle green
|
|
| Australite* |
Australia
|
2.38-2.46
|
1.50-1.52
|
black, brown edge
|
|
| Darwin glass |
Tasmania
|
2.75-2.96
|
1.47-1.48
|
green, black
|
|
| Javaite |
Java
|
2.43-2.45
|
1.509
|
black
|
|
| Billitonite |
Billiton Island (near Borneo)
|
2.46-2.51
|
1.51-1.53
|
black
|
|
| Indochinite* |
Indochina
|
2.40-2.44
|
1.49-1.51
|
black
|
|
| Philippinite (rizalite) |
Philippines, especially Luzon
|
2.44-2.45
|
1.513
|
black
|
|
| Ivory Coast tektite |
Ivory Coast
|
2.40-2.51
|
1.50-1.52
|
black
|
|
| Libyan Desert Glass* |
Libya
|
2.21
|
1.462
|
pale greenish yellow
|
|
| Bediasite* |
Gonzales County, Texas
|
2.33-2.43
|
1.48-1.51
|
black
|
|
| Georgia tektite* |
Georgia
|
2.33
|
1.485
|
light olive-green
|
|
| Massachusetts tektite* |
Martha’s Vineyard, Massachusetts
|
2.33
|
1.485
|
light olive-green
|
 |
| Moldavite |
 |
| Moldavite |
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