AllMineralsRock
Epidote Vs. Olivine
Epidote is a popular mineral composed of calcium aluminium iron silicate.[1] Olivine is a very popular mineral series and its chemical composition is magnesium iron silicate.[2]
Quick Facts on Differences of Epidote and Olivine
For a quick recap of the differences epidote and olivine:- While both epidote and olivine can be translucent or transparent, epidote can be opaque.
- In terms of crystallography, epidote is monoclinic while olivine is orthorhombic.
- For chemical formulas, epidote can be Ca2(Al or Fe)2(SiO4)3(OH) while olivine can be Mg3(SiO4)(F or OH)2.
- While both epidote and olivine can be vitreous, in terms of luster, epidote can be dull, pearly or resinous.
- Epidote streaks white while olivine streaks colorless.
- While both epidote and olivine can be commonly brown, green or yellow, epidote can be commonly red.
Quick Facts on Similarities of Epidote and Olivine
The similarities of epidote and olivine include:- Epidote's rarity is similar to olivine.
- Epidote's specific gravity overlaps with olivine - epidote ranges from 3.21 to 4.2 and olivine ranges from 3.2 to 3.4.
Summary of Epidote
Epidote is a mineral that belongs to the sorosilicate group. It is a common mineral that is found in metamorphic, igneous and sedimentary rocks. Epidote is typically green, but it can also be yellow-brown, black or colorless. The mineral has a hardness of 6 to 7 on the Mohs scale and has a vitreous to resinous luster. Epidote is commonly found in prismatic or tabular crystal habit and can also occur in massive or granular form.Summary of Olivine
Olivine is a common mineral found in igneous and metamorphic rocks. It is a silicate mineral that is made up of magnesium, iron, and silica. Olivine is usually green in color and has a glassy luster. It is a relatively hard mineral, with a Mohs hardness of 6.5 to 7, making it a popular choice for use in jewelry.Table Comparison of Epidote vs Olivine
| Epidote (src) | Olivine (src) | |
|---|---|---|
| Transparency | transparent, translucent, opaque | transparent, translucent |
| Chemical Formula | Ca2(Al,Fe)2(SiO4)3(OH) | Mg3(SiO4)(F,OH)2 |
| Chemical Composition | calcium aluminium iron silicate | magnesium iron silicate |
| Specific Gravity | 3.21, 4.2 | 3.2, 3.4 |
| Streak | white | colorless |
| Crystallography | monoclinic | orthorhombic |
| Hydrous | No | No |
| Colors | common: green, brown, yellow, red sometimes: gray, black, white, colorless less common: pale, pink, rose |
common: green, brown, yellow sometimes: white, colorless less common: gray, orange |
| Category | sorosilicate | nesosilicate |
| Birefringence | δ = 0.019–0.046 | δ = 0.040 |
| Fracture | conchoidal, uneven | conchoidal |