Ohmilite is a rare strontium-titanium silicate typically found in the miarolitic cavities of alkaline igneous rocks. It is highly sought after by micromounters for its delicate, tabular crystal clusters which are often associated with rare pegmatite minerals.
Is this ohmilite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch ohmilite with a known reference. Ohmilite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: light pink.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals, radiating aggregates.
Often confused with
Ohmilite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside ohmilite
Minerals reported to co-occur with ohmilite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Sr₃Ti(Si₂O₆)₂O(H₂O)₂
- Mohs hardness
- 3.5
- Density
- 3.38 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Semitransparent
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals, radiating aggregates
- Cleavage
- Perfect on {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In an amphibolite-quartz-albitite dike cutting serpentinite
Where rockhounds find ohmilite
Classic worldwide localities
- Ohmi, Niigata Prefecture, Japan
Field-hunting tip
Where it forms: In an amphibolite-quartz-albitite dike cutting serpentinite. If you start seeing magnesio-riebeckite, quartz, albite in float, you are in the right ground. Typical habit: tabular crystals, radiating aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify ohmilite?+
Where is ohmilite found?+
What rocks look like ohmilite?+
What minerals are found with ohmilite?+
What kind of rock does ohmilite form in?+
What is ohmilite used for?+
Find ohmilite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
