Comparison · Materials vs Igneous Rocks
Aura Quartz vs Rainbow Obsidian
Aura Quartz and Rainbow Obsidian are easy to confuse. Aura Quartz is harder (Mohs 7) than Rainbow Obsidian (Mohs 5.5), so Aura Quartz will scratch Rainbow Obsidian and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Aura Quartz and Rainbow Obsidian
- Aura Quartz is harder (Mohs 7) than Rainbow Obsidian (Mohs 5.5), so Aura Quartz will scratch Rainbow Obsidian and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will.
- Streak color differs: Aura Quartz leaves a white to colorless streak on unglazed porcelain, Rainbow Obsidian leaves white.
- Luster is different: Aura Quartz is metallic while Rainbow Obsidian is vitreous.
- Hold a thin edge to the light: Aura Quartz is translucent, Rainbow Obsidian is opaque.
- They overlap in multicolored, yellow, and purple, but Aura Quartz also comes in blue and Rainbow Obsidian also comes in black and green.
- Well-formed crystals give it away: Aura Quartz is hexagonal, Rainbow Obsidian is amorphous.
Aura Quartz vs Rainbow Obsidian properties
| Property | Aura Quartz | Rainbow Obsidian |
|---|---|---|
| Type | Materials | Igneous Rocks |
| Mohs hardness | 7 | 5.5 |
| Luster | metallic | vitreous |
| Streak | White to colorless | White |
| Transparency | translucent | opaque |
| Specific gravity | 2.65 | 2.4 |
| Crystal system | hexagonal | amorphous |
| Common colors | Iridescent, Blue, Rainbow, Gold, Purple | Black with rainbow sheen, Purple, Green, Gold |
| Rarity | common | uncommon |
| Typical specimen value | $5–$180+ | $10–$200+ |
Which is more valuable?
Rainbow Obsidian is usually the more valuable of the two: a typical collector specimen runs about $50 against $25 for Aura Quartz, and premium Rainbow Obsidian can reach $200 or more.
About Aura Quartz
Aura Quartz is treated quartz with a thin metallic coating that creates bright blue, rainbow, or iridescent surface color.
About Rainbow Obsidian
Rainbow obsidian is a type of volcanic glass that displays bands of colorful iridescence when polished and viewed in bright light.
Aura Quartz vs Rainbow Obsidian FAQ
Is Aura Quartz the same as Rainbow Obsidian?
No. Aura Quartz is a material while Rainbow Obsidian is a igneous rock. Aura Quartz is harder (Mohs 7) than Rainbow Obsidian (Mohs 5.5), so Aura Quartz will scratch Rainbow Obsidian and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will.
How can you tell Aura Quartz from Rainbow Obsidian?
Aura Quartz is harder (Mohs 7) than Rainbow Obsidian (Mohs 5.5), so Aura Quartz will scratch Rainbow Obsidian and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will. Streak color differs: Aura Quartz leaves a white to colorless streak on unglazed porcelain, Rainbow Obsidian leaves white. Luster is different: Aura Quartz is metallic while Rainbow Obsidian is vitreous.
Which is harder, Aura Quartz or Rainbow Obsidian?
Aura Quartz is harder: Mohs 7 against Mohs 5.5 for Rainbow Obsidian.
Which is more valuable, Aura Quartz or Rainbow Obsidian?
Rainbow Obsidian is usually the more valuable of the two: a typical collector specimen runs about $50 against $25 for Aura Quartz, and premium Rainbow Obsidian can reach $200 or more.
