Tantalcarbide is an extremely rare, hard, and dense mineral often found in association with metallic meteorites or unique heavy mineral placer deposits. It typically occurs as microscopic grains or anhedral inclusions, making it a prized discovery for advanced mineralogists and meteoritic researchers.

Hardness

6-7

Mohs

Luster

Metallic

Transparency

Opaque

mineralrare

Tantalcarbide

Hardness: 6-7
Luster: Metallic
Transparency: Opaque

Is this tantalcarbide?

4-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 tantalcarbide with a known reference. Tantalcarbide sits at Mohs 6-7, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Luster: metallic.
3
Match the color range
Compare against the expected color range: yellow gray.
4
Look at form & habit
Crystal system: cubic. Typical habit: anhedral grains, massive.

Often confused with

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

mineral

Tantalite

Mohs 6

How to tell apart: Luster reads metallic on Tantalcarbide and submetallic to resinous on Tantalite.

How to tell apart: Luster reads metallic on Tantalcarbide and submetallic on Columbite.

Compare →

Often found alongside tantalcarbide

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

All properties

Chemical formula: TaC
Mohs hardness: 6-7
Density: 14.5 g/cm³
Colors: Yellow gray
Luster: Metallic
Transparency: Opaque
Crystal system: Cubic
Crystal habit: Anhedral grains, massive
Rarity: Rare
Uses: Collector, Scientific
Host rock: In placer concentrates from a “gold-washing operation”

Where rockhounds find tantalcarbide

Classic worldwide localities

Nizhnii Tagil, Middle Urals, Russia

Field-hunting tip

Where it forms: In placer concentrates from a “gold-washing operation”. If you start seeing native gold, α-fe, nickel in float, you are in the right ground. Typical habit: anhedral grains, massive. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify tantalcarbide?+

Mohs hardness is 6-7. Luster: metallic. Common colors include yellow gray.

Where is tantalcarbide found?+

Notable localities include Nizhnii Tagil, Middle Urals, Russia.

What rocks look like tantalcarbide?+

Tantalcarbide is most often confused with Tantalite, Columbite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with tantalcarbide?+

Tantalcarbide commonly co-occurs with Native gold, Α-Fe, Nickel, Fe-Ta-Nb, Fe-Sn alloys, Apatite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does tantalcarbide form in?+

Where it forms: In placer concentrates from a “gold-washing operation”. Working float back to the host body is the standard way to chase a fresh occurrence.

What is tantalcarbide used for?+

Tantalcarbide is used in collector, scientific.

Find tantalcarbide on the map

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