Epidote-(Sr) is a rare strontium-bearing member of the epidote group, often indistinguishable from standard epidote without chemical analysis. It typically forms in metamorphic environments where strontium-rich fluids are present, frequently occurring as small, prismatic, yellowish-brown crystals.

Hardness

6-7

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareEpidote Group family

Epidote-(Sr)

Hardness: 6-7
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this epidote-(sr)?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch epidote-(sr) with a known reference. Epidote-(Sr) sits at Mohs 6-7 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Epidote-(Sr) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Epidote-(Sr) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: yellow, brown, greenish-yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals, granular.

Often confused with

Epidote-(Sr) vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside epidote-(sr)

Minerals reported to co-occur with epidote-(sr). Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: CaSrAl₂Fe³⁺(Si₂O₇)(SiO₄)O(OH)
Mohs hardness: 6-7
Density: 3.5-3.6 g/cm³
Colors: Yellow Brown Greenish-yellow
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals, Granular
Cleavage: Perfect in One Direction
Rarity: Rare
Uses: Collector
Host rock: Metamorphic Rocks, Skarn Deposits
Typical price: $20-150 for rare specimen pieces

Where rockhounds find epidote-(sr)

Classic worldwide localities

Japan
Sweden
Italy

Field-hunting tip

Look in metamorphic rocks, skarn deposits country — that is the host setting where epidote-(sr) typically forms. If you start seeing calcite, quartz, garnet in float, you are in the right ground. Field specimens usually show a prismatic crystals, granular habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify epidote-(sr)?+

Mohs hardness is 6-7. It typically shows a vitreous luster. The streak is white. Common colors include yellow, brown, greenish-yellow.

Where is epidote-(sr) found?+

Notable localities include Japan; Sweden; Italy.

How much is epidote-(sr) worth?+

Typical asking prices fall in the range of $20-150 for rare specimen pieces. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like epidote-(sr)?+

Epidote-(Sr) is most often confused with Epidote, Clinozoisite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with epidote-(sr)?+

Epidote-(Sr) commonly co-occurs with Calcite, Quartz, Garnet. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does epidote-(sr) form in?+

Epidote-(Sr) typically forms in metamorphic rocks, skarn deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is epidote-(sr) used for?+

Epidote-(Sr) is used in collector.

Find epidote-(sr) on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.