Bredigite is an uncommon nesosilicate mineral typically found in high-temperature contact metamorphic environments and artificial slag. It most often occurs as small granular aggregates or massive patches, making it a challenging species for non-specialist collectors to identify without analytical verification.

Hardness

5.5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareOlivine Group family

Bredigite

Hardness: 5.5-6
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this bredigite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch bredigite with a known reference. Bredigite sits at Mohs 5.5-6 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Bredigite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Bredigite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, gray.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: granular, massive, rarely distinct crystals.

Often confused with

Bredigite vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside bredigite

Minerals reported to co-occur with bredigite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: Ca₇Mg(SiO₄)₄
Mohs hardness: 5.5-6
Density: 3.39-3.41 g/cm³
Colors: Colorless White Gray
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Granular, Massive, Rarely Distinct Crystals
Cleavage: None
Rarity: Rare
Uses: Collector, Scientific Research
Host rock: Contact Metamorphic Zones, High-temperature Furnace Slag
Typical price: n/a (rarely traded)

Where rockhounds find bredigite

Classic worldwide localities

Bredig quarry, Pennsylvania, USA
Hatrurim Formation, Israel
Cimini Mountains, Italy

Field-hunting tip

Look in contact metamorphic zones, high-temperature furnace slag country — that is the host setting where bredigite typically forms. If you start seeing larnite, merwinite, calcite in float, you are in the right ground. Field specimens usually show a granular, massive, rarely distinct crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify bredigite?+

Mohs hardness is 5.5-6. It typically shows a vitreous luster. The streak is white. Common colors include colorless, white, gray.

Where is bredigite found?+

Notable localities include Bredig quarry, Pennsylvania, USA; Hatrurim Formation, Israel; Cimini Mountains, Italy.

How much is bredigite worth?+

Typical asking prices fall in the range of n/a (rarely traded). Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like bredigite?+

Bredigite is most often confused with Larnite, Merwinite, Olivine. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with bredigite?+

Bredigite commonly co-occurs with Larnite, Merwinite, Calcite, Gehlenite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does bredigite form in?+

Bredigite typically forms in contact metamorphic zones, high-temperature furnace slag. Working float back to the host body is the standard way to chase a fresh occurrence.

What is bredigite used for?+

Bredigite is used in collector, scientific research.

Find bredigite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.