AllMineralsRock
Sapphire Vs. Spinel
Sapphire 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 Sapphire and Spinel
For a quick recap of the differences sapphire and spinel:- For chemical formulas, sapphire is Al2O3 while spinel is MgAl2O4.
- While both sapphire and spinel can be vitreous, in terms of luster, sapphire can be adamantine.
- Sapphire streaks colorless while spinel streaks white.
- Sapphire can be commonly blue or green while spinel can be commonly red.
- Sapphire's rarity is less rare than spinel.
- Sapphire's hardness is higher than spinel - sapphire is 9 and spinel ranges from 7.5 to 8 on the Moh's scale.
- Sapphire's specific gravity is higher than spinel - sapphire ranges from 3.99 to 4 and spinel ranges from 3.58 to 3.58.
Quick Facts on Similarities of Sapphire and Spinel
The similarities of sapphire and spinel include:- Sapphire and spinel both can be opaque, translucent or transparent.
Summary of Sapphire
Sapphire is a precious mineral that belongs to the corundum family. It is a variety of aluminum oxide that is distinguished by its blue color, although it can also be found in other colors such as pink, yellow, green, and purple. Sapphire is one of the hardest minerals in the world, with a hardness of 9 on the Mohs scale, making it an ideal material for use in jewelry and industrial applications.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 Sapphire vs Spinel
| Sapphire (src) | Spinel (src) | |
|---|---|---|
| Transparency | transparent, translucent, opaque | transparent, translucent, opaque |
| Chemical Formula | Al2O3 | MgAl2O4 |
| Chemical Composition | silicon dioxide | magnesium aluminum oxide |
| Specific Gravity | 3.99, 4, 4.1 | 3.58, 3.58, 3.61, 3.98 |
| Hardness | 9 | 7.5, 8 |
| Streak | colorless | white |
| Refractive Index | 1.757, 1.779 | 1.719, 1.92 |
| Hydrous | No | No |
| Colors | common: green, blue sometimes: pink, amber, yellow less common: gray, black, brown, white, orange, purple, violet, colorless, red, gold, multicolor |
common: red sometimes: brown, green, orange, colorless less common: blue, gray, pink, rose, black, lilac, white, purple, yellow |
| Solubility | Insoluble | Insoluble |
| Fracture | conchoidal | conchoidal |