Ivsite is an extremely rare sulfate mineral found exclusively at the historic cryolite deposit in Ivigtut, Greenland. It typically occurs as small, delicate colorless platy crystals or crusts associated with other secondary minerals in the cryolite mine environment.
Is this ivsite?
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 ivsite with a known reference. Ivsite sits at Mohs 2, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Ivsite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Ivsite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: colorless.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: platy crystals, crusts.
Often confused with
Ivsite vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Luster reads pearly on Ivsite and vitreous on Chalcanthite.

How to tell apart: Antlerite is the harder of the two (Mohs 3.5 vs. 2); streak differs, so Ivsite leaves white, Antlerite leaves light green; luster reads pearly on Ivsite and vitreous on Antlerite.
Often found alongside ivsite
Minerals reported to co-occur with ivsite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₄Cu₅(SO₄)₅Cl₂·10H₂O
- Mohs hardness
- 2
- Density
- 2.41 g/cm³
- Colors
- Streak
- White
- Luster
- Pearly
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Platy Crystals, Crusts
- Cleavage
- Perfect in One Direction
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Cryolite Deposits
Where rockhounds find ivsite
Classic worldwide localities
- Naboko outburst, Tolbachik fissure eruption, Kamchatka Peninsula, Russia
Field-hunting tip
Look in cryolite deposits country, the host setting where ivsite typically forms. If you start seeing cryolite, thomsenolite, siderite in float, you are in the right ground. Field specimens usually show a platy crystals, crusts habit, so train your eye for that shape before scanning the outcrop.




