AllMineralsRock
Quartz Vs. Spinel
Quartz is a very popular gemstone composed of silicon dioxide.[1] Spinel is also a very popular gemstone and its chemical composition is magnesium aluminum oxide.[2]
Quick Facts on Differences of Quartz and Spinel
For a quick recap of the differences quartz and spinel:- For chemical formulas, quartz is SiO2 while spinel is MgAl2O4.
- While both quartz and spinel can be vitreous, in terms of luster, quartz can be greasy or waxy.
- While both quartz and spinel can be commonly red, quartz is often yellow.
- Quartz's rarity is less rare than spinel.
- Quartz's hardness is lower than spinel - quartz is 7 and spinel ranges from 7.5 to 8 on the Moh's scale.
- Quartz's specific gravity is lower than spinel - quartz ranges from 2.651 to 2.91 and spinel ranges from 3.58 to 3.58.
Quick Facts on Similarities of Quartz and Spinel
The similarities of quartz and spinel include:- Quartz and spinel both can be opaque, translucent or transparent.
- Quartz and spinel both streak white.
Summary of Quartz
Quartz is a mineral that is composed of silicon and oxygen atoms arranged in a continuous framework of SiO4 silicon-oxygen tetrahedra. It is one of the most abundant minerals found in the Earth's crust. Quartz can be found in a variety of colors such as white, pink, purple, brown, gray, and black. It is also known for its unique crystal structure, which is hexagonal in shape, and its hardness, which is 7 on the Mohs scale.Summary of Spinel
Spinel is a mineral that is commonly found in a variety of geological environments. It is a magnesium aluminum oxide mineral that can be found in a range of colors, including red, blue, green, yellow, and purple. It is often used as a gemstone due to its vibrant colors and durability, which makes it an excellent choice for jewelry.Table Comparison of Quartz vs Spinel
| Quartz (src) | Spinel (src) | |
|---|---|---|
| Transparency | transparent, translucent, opaque | transparent, translucent, opaque |
| Chemical Formula | SiO2 | MgAl2O4 |
| Chemical Composition | silicon dioxide | magnesium aluminum oxide |
| Specific Gravity | 2.651, 2.91 | 3.58, 3.58, 3.61, 3.98 |
| Hardness | 7 | 7.5, 8 |
| Streak | white | white |
| Refractive Index | 1.544, 1.553 | 1.719, 1.92 |
| Hydrous | No | No |
| Colors | common: red, yellow sometimes: blue, gray, pink, black, brown, green, white, orange, purple, violet, colorless, multicolor |
common: red sometimes: brown, green, orange, colorless less common: blue, gray, pink, rose, black, lilac, white, purple, yellow |
| Solubility | Insoluble at STP | Insoluble |
| Category | silicate | spinel |
| Fracture | conchoidal, uneven | conchoidal |