Smelted 'Quartz' (Glass)
Smelted 'Quartz' (Glass) is glass (often silica-based), (fused silica/soda-lime glass). In the hand, it rates 5.5 to 6 on the Mohs scale, and it runs water clear and pale yellow ('citrine'). Implausibly flawless, dead-clear towers and spheres, no veils, no striations, but round gas bubbles and faint flow lines inside.
The geology.
Smelted 'Quartz' (Glass) carries the formula (fused silica/soda-lime glass). It belongs to the amorphous (none) system. The trade files it under glass (often silica-based).
It sits at 5.5 to 6 on the Mohs scale. The surface reads vitreous. Light behaviour is transparent. Specific gravity runs 2.2 to 2.6. The streak is white. It breaks with conchoidal fracture.
Implausibly flawless, dead-clear towers and spheres, no veils, no striations, but round gas bubbles and faint flow lines inside.
Common cuts are large flawless towers, spheres, points or 'citrine' generators.
The origins.
Furnace-made, primarily China; sold at gem shows in tower and sphere form.
On value, the database notes: worth glass prices only.
Traditional associations.
In energy work traditions, sold with quartz's amplification claims, buyers deserve to know it is kiln glass.
Included for completeness. Tradition is worth knowing about, and it is worth keeping separate from the mineralogy.
Spotting the real thing.
Implausibly flawless, dead-clear towers and spheres, no veils, no striations, but round gas bubbles and faint flow lines inside.
This IS the fake: huge flawless 'quartz' or 'citrine' towers at bargain prices are the give-away combination.
| Looks like | How to tell them apart |
|---|---|
| Natural clear quartz | Real quartz has wisps, veils, and cross-face striations; smelted glass is empty-clear with bubbles |
| Lab-grown quartz | Lab quartz is true crystal (no bubbles, has crystal faces); smelted glass is molded/carved |
| Natural citrine | Pale yellow glass towers lack any zoning or crystal structure |
At-home tests.
These checks cost nothing. Daylight, a 10x loupe and a little patience are the whole kit for smelted 'quartz' (glass).
| Test | What you should see |
|---|---|
| Loupe | round bubbles = glass, every time |
| By eye | Too-perfect clarity in large cheap pieces |
| By eye | No striations on 'crystal faces' |
| By touch | Glass warms faster than quartz in hand |
Stop short of anything that leaves a mark. A gemologist can answer the rest without damaging the stone.
Care & handling.
At 5.5 to 6 on the Mohs scale it handles careful wear but scratches against quartz and dust. Store it separately and take rings off before rough work.
It breaks with conchoidal fracture, which is worth knowing before you set it or drop it.
Skip the ultrasonic. Lukewarm water, mild soap and a soft cloth handle routine cleaning without risk.
A deeper look.
Extended detail on composition, sourcing, authentication and market value.
The physical record
The formula on record is (fused silica/soda-lime glass). Crystal system: Amorphous (none). Specific gravity: 2.2 to 2.6. Streak: White. Cleavage and fracture: Conchoidal fracture.
How it reaches the market
Furnace-made, primarily China; sold at gem shows in tower and sphere form.
What it gets confused with
Natural clear quartz: Real quartz has wisps, veils, and cross-face striations; smelted glass is empty-clear with bubbles. Lab-grown quartz: Lab quartz is true crystal (no bubbles, has crystal faces); smelted glass is molded/carved. Natural citrine: Pale yellow glass towers lack any zoning or crystal structure.
What it is worth
Worth glass prices only.
Where buyers get caught
This IS the fake: huge flawless 'quartz' or 'citrine' towers at bargain prices are the give-away combination.
One more thing
The name 'smelted quartz' is seller spin, melting quartz sand produces glass, and glass it remains.
An education-first guide.
We do not carry smelted 'quartz' (glass). This page exists because the question comes up and the honest answer is worth writing down, whether or not there is anything here to sell you.
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