AllMineralsRock
Aquamarine Vs. Tourmaline
Aquamarine is a very popular gemstone composed of beryllium aluminum silicate.[1] Tourmaline is also a very popular gemstone and its chemical composition is boron silicate.[2]
Quick Facts on Differences of Aquamarine and Tourmaline
For a quick recap of the differences aquamarine and tourmaline:- While both aquamarine and tourmaline is hexagonal, in terms of crystallography, tourmaline can be trigonal.
- For chemical formulas, aquamarine is Be3Al2Si6O18 while tourmaline can be (Ca, Al, B)6O18(OH, Cr, F)4, Fe, Fe, K, Li, Mg, Mn)3(Al, Na)(Al or V)6(BO3)3(Si.
- Aquamarine streaks colorless while tourmaline streaks white.
- Aquamarine can be commonly blue or green while tourmaline can be commonly red.
- Aquamarine's specific gravity is lower than tourmaline - aquamarine ranges from 2.66 to 2.8 and tourmaline ranges from 2.82 to 3.9.
Quick Facts on Similarities of Aquamarine and Tourmaline
The similarities of aquamarine and tourmaline include:- Aquamarine and tourmaline both can be opaque, translucent or transparent.
- In terms of luster, aquamarine and tourmaline both are vitreous.
- Aquamarine's rarity is similar to tourmaline.
- Aquamarine's hardness overlaps with tourmaline - aquamarine ranges from 7.5 to 8 and tourmaline ranges from 7 to 7.5 on the Moh's scale.
Summary of Aquamarine
Aquamarine is a blue-green variety of the mineral beryl. It is a popular gemstone because of its beautiful color and clarity. The name aquamarine comes from the Latin words aqua, meaning water, and marina, meaning sea. This is because the color of aquamarine is similar to the color of the ocean.Summary of Tourmaline
Tourmaline is a mineral that belongs to the silicate group and is known for its unique crystal structure and the wide range of colors it comes in. It is a complex mineral that contains boron, aluminum, and other elements. Tourmaline is found in many different parts of the world, including Brazil, Afghanistan, Pakistan, and the United States. The mineral can be identified by its prismatic crystal habit, which means that it has a long, column-like shape with flat faces on either end.Table Comparison of Aquamarine vs Tourmaline
| Aquamarine (src) | Tourmaline (src) | |
|---|---|---|
| Transparency | transparent, translucent, opaque | transparent, translucent, opaque |
| Chemical Formula | Be3Al2Si6O18 | (Ca,K,Na)(Al,Fe,Li,Mg,Mn)3(Al,Cr,Fe,V)6(BO3)3(Si,Al,B)6O18(OH,F)4 |
| Chemical Composition | beryllium aluminum silicate | boron silicate |
| Specific Gravity | 2.66, 2.8 | 2.82, 3.9 |
| Hardness | 7.5, 8 | 7, 7.5 |
| Streak | colorless | white |
| Crystallography | hexagonal | hexagonal, trigonal |
| Refractive Index | 1.567, 1.59 | 1.603, 1.82 |
| Hydrous | No | No |
| Colors | common: blue, green |
common: red sometimes: blue, black less common: gray, pink, brown, green, white, orange, purple, violet, yellow, colorless, multicolor |
| Fracture | conchoidal, uneven | conchoidal, uneven |