Sakuraiite is an extremely rare indium-bearing sulfide mineral that typically occurs as small inclusions or massive aggregates in hydrothermal tin-polymetallic deposits. It is best identified through laboratory analysis, as it is megascopically indistinguishable from other dark, metallic sulfides like sphalerite or stannite.
Is this sakuraiite?
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 sakuraiite with a known reference. Sakuraiite sits at Mohs 3.5-4, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Sakuraiite leaves a black streak.
- 3Read the lusterHold the specimen under a strong light. Sakuraiite typically shows a metallic luster.
- 4Match the color rangeCompare against the expected color range: gray, black.
- 5Look at form & habitCrystal system: tetragonal. Typical habit: massive, granular.
Often confused with
Sakuraiite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Sakuraiite leaves black, Sphalerite leaves white to yellow-brown; luster reads metallic on Sakuraiite and resinous to submetallic on Sphalerite.
How to tell apart: Streak differs, so Sakuraiite leaves black, Chalcopyrite leaves greenish-black.
Often found alongside sakuraiite
Minerals reported to co-occur with sakuraiite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Cu,Zn,Fe,In,Sn)₄S₄
- Mohs hardness
- 3.5-4
- Density
- 4.5-4.8 g/cm³
- Streak
- Black
- Luster
- Metallic
- Transparency
- Opaque
- Crystal system
- Tetragonal
- Crystal habit
- Massive, Granular
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Hydrothermal Veins
- Typical price
- $50-300 per specimen
Where rockhounds find sakuraiite
Classic worldwide localities
- Ikuno mine, Japan
- Toyoha mine, Japan
Field-hunting tip
Look in hydrothermal veins country, the host setting where sakuraiite typically forms. If you start seeing cassiterite, sphalerite, chalcopyrite in float, you are in the right ground. Field specimens usually show a massive, granular habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify sakuraiite?+
Where is sakuraiite found?+
How much is sakuraiite worth?+
Is sakuraiite safe to handle?+
What rocks look like sakuraiite?+
What minerals are found with sakuraiite?+
What kind of rock does sakuraiite form in?+
What is sakuraiite used for?+
Find sakuraiite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
