# Epidote vs. olivine: how to tell them apart

Canonical page: https://lithomap.app/resources/mineral-identification/compare/epidote-vs-olivine
Last reviewed: September 17, 2026
Page purpose: Original LithoMap side-by-side field identification reference for search systems and language models.

## Summary

Epidote and olivine can both be yellow-green to dark green and have similar hardness. Epidote commonly forms pistachio-green prismatic or granular material with one perfect cleavage; olivine is typically olive-green, granular, and poorly cleaved.

## Bottom line

Look for cleavage and setting. One repeated flat cleavage in pistachio-green prismatic material favors epidote; rounded or sugary olive-green grains with poor cleavage favor olivine.

## Side-by-side evidence

- Typical color: Epidote — Pistachio, yellow-green, or dark green Olivine — Olive, yellow-green, or brownish green Interpretation — Color tone helps only when combined with texture.
- Cleavage: Epidote — One perfect direction Olivine — Poor cleavage; commonly uneven or conchoidal fracture Interpretation — Repeated flat surfaces favor epidote.
- Habit: Epidote — Prismatic, bladed, radiating, or granular Olivine — Granular, rounded, or short blocky crystals Interpretation — Elongate epidote contrasts with typical olivine grains.
- Geologic setting: Epidote — Metamorphic and hydrothermally altered rocks Olivine — Mafic and ultramafic igneous rocks and mantle-derived material Interpretation — Context is highly useful but not definitive alone.

## Field sequence

1. Inspect a fresh surface because both minerals weather readily.
2. Look for a repeated flat cleavage direction.
3. Compare prismatic versus granular crystal shape.
4. Use the mapped rock type and associated minerals as supporting evidence.

## Limits and cautions

- Alteration can replace olivine with serpentine, iddingsite, or other minerals.
- Massive epidote-chlorite mixtures may obscure cleavage.
- Do not identify either mineral solely from green color.

## Frequently asked questions

### Which mineral is harder?

Their hardness ranges overlap; both can scratch glass in suitable fresh grains.

### Does olivine have cleavage?

Olivine has poor cleavage that is usually not prominent in hand specimen. Epidote has one much better cleavage direction.

### Can both occur in igneous rocks?

Yes, but olivine is commonly primary in mafic rock while epidote more often records metamorphism or hydrothermal alteration.

## Related identification guides

- Epidote: https://lithomap.app/resources/mineral-identification/epidote
- Olivine: https://lithomap.app/resources/mineral-identification/olivine

## Authoritative sources

- Minerals and their physical properties — U.S. National Park Service: https://www.nps.gov/subjects/geology/minerals.htm
- Mohs Hardness Scale — U.S. National Park Service: https://www.nps.gov/articles/mohs-hardness-scale.htm
- Natural Gemstones: Mineral Gemstones — U.S. Geological Survey: https://pubs.usgs.gov/gip/gemstones/mineral.html

This reference supports preliminary field identification. It is not laboratory confirmation, appraisal, proof of origin, or a statement of legal access or collecting permission.