The facts
What indochinite actually is
Mineralogically, indochinite is a tektite of the Australasian strewn field, formed approximately 790,000 years ago by an as-yet-unlocated impact — SiO2 approx. 70-75%, with Al2O3, FeO, MgO, CaO and K2O; very low water, crystallising in the amorphous system.
The colour is caused by fe2+ and Fe3+; opaque black in the hand, deep brown in thin splinters. That is worth knowing because it determines what heating, light and time can and cannot do to the stone.
A refractometer reads 1.49-1.52, and the specific gravity sits near 2.35-2.50; cleavage is none; conchoidal fracture with a pitted, grooved natural surface.
Where indochinite comes from
The recognised sources are Ubon Ratchathani and Khorat Plateau, northeastern Thailand, Champasak and southern Laos, Guangdong and Hainan, China and Java and Bikol, Indonesia and the Philippines (philippinites / rizalites).
Origin affects price in this material, so we name the locality on every quote rather than the country. "African" or "Asian" tells a buyer nothing.
How indochinite is treated
Untreated. Abundant and cheap, which is why it is used to fake more valuable tektites - carved and re-etched indochinite is sold as moldavite substitute and as 'Agni Manitite' and other marketing names. Genuine tektites are non-magnetic to a strong magnet, unlike most slag. Not CITES; some source countries restrict bulk export of geological material.
None of this is a problem when it is said out loud. It becomes one the moment it is left out.
What indochinite is confused with
The usual confusions are Obsidian (higher water content, different chemistry), Industrial slag glass, Carved indochinite sold under invented trade names and Meteorites (tektites are terrestrial melt, not extraterrestrial).
The separation is rarely a matter of opinion: refractive index 1.49-1.52 and specific gravity 2.35-2.50 settle most of it in a minute, and magnification settles the rest.
What indochinite is used for
Indochinite is bought by mineral collecting, jewellery and decorative objects — and each of those trades wants a different form of the same material.
We quote each application in the unit that trade actually buys in, by the specimen, by the carat or by the piece.
Durability and care
Indochinite is 5.5-6.5 on the Mohs scale, with none; conchoidal fracture with a pitted, grooved natural surface cleavage.
With no cleavage plane to worry about, the practical limit is abrasion rather than breakage, and it takes daily wear well.
Warm water, mild soap and a soft brush. Avoid ultrasonic cleaners on anything fracture-filled, stabilised, dyed or visibly included.
What indochinite costs
Indicative pricing for indochinite is $0.20-2 per gram for common material; fine shapes and large specimens $2-15 per gram.
That is a range, not a quote. Colour, size, clarity, cut and origin move the figure a long way inside it, and the only honest price is one given against a specific stone. Send us what you need and we will price it.
Questions
Is indochinite treated, and how?
Untreated. Abundant and cheap, which is why it is used to fake more valuable tektites - carved and re-etched indochinite is sold as moldavite substitute and as 'Agni Manitite' and other marketing names. Genuine tektites are non-magnetic to a strong magnet, unlike most slag. Not CITES; some source countries restrict bulk export of geological material.
Where does indochinite come from?
Ubon Ratchathani and Khorat Plateau, northeastern Thailand, Champasak and southern Laos, Guangdong and Hainan, China and Java and Bikol, Indonesia and the Philippines (philippinites / rizalites). Origin affects price, so we name the locality rather than the country on every quote.
Is indochinite hard enough to wear every day?
Yes. At 5.5-6.5 on the Mohs scale with no cleavage plane, it handles daily wear well. The practical limit is gradual abrasion rather than chipping.
How much does indochinite cost?
Indicatively $0.20-2 per gram for common material; fine shapes and large specimens $2-15 per gram. Colour, size, clarity and origin move the price a long way within that, so treat it as a range and ask for a quote against a specific stone.
What is indochinite confused with?
Most often Obsidian (higher water content, different chemistry), Industrial slag glass, Carved indochinite sold under invented trade names and Meteorites (tektites are terrestrial melt, not extraterrestrial). A refractive index of 1.49-1.52 and a specific gravity near 2.35-2.50 separate it quickly.
What is indochinite used for besides jewellery?
mineral collecting and decorative objects. Each of those trades buys it in a different form and a different unit.
Related stones
Looking for indochinite?
Tell us the size, the quality and what it is for. We source it, photograph it and quote it — with the locality named.
Ask about indochinite