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. Gugiaite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Gugiaite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white, grayish.
- 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
- 3.01 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Tetragonal
- Crystal habit
- Tabular Crystals, Sometimes Dipyramidal
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Skarn Deposits
- Typical price
- $50-500 depending on specimen size and quality
Where rockhounds find gugiaite
Classic worldwide localities
- Gugia Mine, China
Field-hunting tip
Look in skarn deposits country — that is the host setting where gugiaite typically forms. If you start seeing calcite, diopside, vesuvianite in float, you are in the right ground. Field specimens usually show a tabular crystals, sometimes dipyramidal habit, so train your eye for that shape before scanning the outcrop.





