Hemloite is an extremely rare oxide mineral known primarily from its type locality at the Hemlo gold deposit in Ontario, Canada. It typically occurs as minute, opaque, metallic grains associated with hematite and other titanium-bearing minerals in metamorphosed rocks. Due to its scarcity and microscopic nature, it is highly sought after by specialized mineral collectors and professional researchers.

Hardness

6.5-7

Mohs

Luster

Metallic to submetallic

Streak

Black

Transparency

Opaque

mineralrare

Hemloite

Hardness: 6.5-7
Luster: Metallic to submetallic
Streak: Black
Transparency: Opaque

Is this hemloite?

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 hemloite with a known reference. Hemloite sits at Mohs 6.5-7, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: black.
3
Read the luster
Hold the specimen under a strong light. Luster: metallic to submetallic.
4
Match the color range
Compare against the expected color range: black, dark gray, dark brown.
5
Look at form & habit
Crystal system: triclinic. Typical habit: anhedral grains.

Often confused with

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

mineral

Hematite

Mohs 5-6

How to tell apart: Streak differs, so Hemloite leaves black, Hematite leaves cherry-red or reddish brown.

Often found alongside hemloite

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

All properties

Chemical formula: (Ti,V,Fe,Al)₁₂As₂O₂₃(OH)
Mohs hardness: 6.5-7
Density: 4.613 g/cm³
Colors: Black Dark gray Dark brown
Streak: Black
Luster: Metallic to submetallic
Transparency: Opaque
Crystal system: Triclinic
Crystal habit: Anhedral grains
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: In a hydrothermal gold deposit

Where rockhounds find hemloite

Classic worldwide localities

Hemlo gold deposit, in the Page-Williams mine, three km east of Hemlo, Thunder Bay district, Ontario, Canada

Field-hunting tip

Where it forms: In a hydrothermal gold deposit. If you start seeing quartz, barian microcline, pyrite in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify hemloite?+

Mohs hardness is 6.5-7. Luster: metallic to submetallic. The streak is black. Common colors include black, dark gray, dark brown.

Where is hemloite found?+

Notable localities include Hemlo gold deposit, in the Page-Williams mine, three km east of Hemlo, Thunder Bay district, Ontario, Canada.

Is hemloite safe to handle?+

Hemloite contains arsenic and vanadium and calls for real care. Wash your hands afterwards, never grind or breathe the dust, and store it apart from specimens you handle often.

What rocks look like hemloite?+

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

What minerals are found with hemloite?+

Hemloite commonly co-occurs with Quartz, Barian microcline, Pyrite, Molybdenite, Sphalerite, Arsenopyrite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hemloite form in?+

Where it forms: In a hydrothermal gold deposit. Working float back to the host body is the standard way to chase a fresh occurrence.

What is hemloite used for?+

Hemloite is used in collector.

Find hemloite on the map

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