Grossularite is a calcium-aluminum garnet that forms in diverse colors, ranging from the green 'Tsavorite' variety to the orange-brown 'Hessonite'. It is commonly found as well-formed dodecahedral crystals in contact metamorphic rocks like skarns. Collectors often prize it for its high brilliance and clear, well-defined crystal shapes.
Is this grossularite garnet?
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 grossularite garnet with a known reference. Grossularite Garnet sits at Mohs 6.5-7.5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Grossularite Garnet leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Grossularite Garnet typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: green, yellow, brown, orange, colorless.
- 5Look at form & habitCrystal system: cubic. Typical habit: dodecahedral or trapezohedral crystals.
Often confused with
Grossularite Garnet vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside grossularite garnet
Minerals reported to co-occur with grossularite garnet. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ca₃Al₂(SiO₄)₃
- Mohs hardness
- 6.5-7.5
- Density
- 3.5-3.6 g/cm³
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Cubic
- Crystal habit
- Dodecahedral or Trapezohedral Crystals
- Cleavage
- None
- Fluorescence
- Orange Under LW UV
- Rarity
- Common
- Uses
- Gemstone, Collector
- Host rock
- Metamorphosed Limestone and Skarn Deposits
- Typical price
- $10-100 per carat for gem quality, $20-200 for specimens
Where rockhounds find grossularite garnet
3 mapped spotsClassic worldwide localities
- Mexico
- Canada
- Kenya
- Tanzania
- USA
Field-hunting tip
Look in metamorphosed limestone and skarn deposits country, the host setting where grossularite garnet typically forms. If you start seeing diopside, calcite, epidote in float, you are in the right ground. Field specimens usually show a dodecahedral or trapezohedral crystals habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Oregon, Pennsylvania, Utah. Start trip planning there.
Common questions
How do you identify grossularite garnet?+
Where is grossularite garnet found?+
Can I find grossularite garnet in the United States?+
How much is grossularite garnet worth?+
What rocks look like grossularite garnet?+
What minerals are found with grossularite garnet?+
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Find grossularite garnet on the map
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