Gugiaite is a very rare member of the melilite group, typically occurring in skarn environments. It is most easily identified by its occurrence at the type locality in the Gugia mine, where it forms small, glassy tabular crystals.
Is this gugiaite?
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 gugiaite with a known reference. Gugiaite sits at Mohs ~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: colorless.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: tabular crystals, sometimes dipyramidal.
Often confused with
Gugiaite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside gugiaite
Minerals reported to co-occur with gugiaite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₂BeSi₂O₇
- Mohs hardness
- ~5
- Density
- 3.034 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Tetragonal
- Crystal habit
- Tabular crystals, sometimes dipyramidal
- Cleavage
- Perfect on {010}, distinct on {001}, poor on {110}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In cavities in skarns and melanite adjacent to an alkalic syenite
Where rockhounds find gugiaite
Classic worldwide localities
- Village of Gugia, otherwise unlocated in China
Field-hunting tip
Where it forms: In cavities in skarns and melanite adjacent to an alkalic syenite. If you start seeing orthoclase, vesuvianite, aegirine in float, you are in the right ground. Typical habit: tabular crystals, sometimes dipyramidal. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify gugiaite?+
Where is gugiaite found?+
Is gugiaite safe to handle?+
What rocks look like gugiaite?+
What minerals are found with gugiaite?+
What kind of rock does gugiaite form in?+
What is gugiaite used for?+
Find gugiaite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
