Macphersonite is a rare lead sulfate-carbonate mineral typically found in the oxidation zones of lead deposits. It is most famously identified from the Leadhills-Wanlockhead district in Scotland, where it forms small, delicate crystals often associated with leadhillite and susannite.

Hardness

2.5-3

Mohs

Luster

Adamantine to resinous

Streak

White

Transparency

Semitransparent

mineralrareLeadhillite-Susannite Group family

Macphersonite

Hardness: 2.5-3
Luster: Adamantine to resinous
Streak: White
Transparency: Semitransparent

Is this macphersonite?

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 macphersonite with a known reference. Macphersonite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: adamantine to resinous.
4
Match the color range
Compare against the expected color range: white, pale amber brown, colorless.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: pseudo hexagonal, tabular.

Often confused with

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

mineral

Leadhillite

Mohs 2.5-3

How to tell apart: Luster reads adamantine to resinous on Macphersonite and resinous to adamantine, pearly on {001} on Leadhillite.

Often found alongside macphersonite

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

All properties

Chemical formula: Pb₄(SO₄)(CO₃)₂(OH)₂
Mohs hardness: 2.5-3
Density: 6.50-6.55 g/cm³
Colors: WhitePale amber brownColorless
Streak: White
Luster: Adamantine to resinous
Transparency: Semitransparent
Crystal system: Orthorhombic
Crystal habit: Pseudo hexagonal, tabular
Cleavage: On {010}, perfect
Fluorescence: Strong yellow under SW and LW UV
Rarity: Rare
Uses: Collector
Host rock: An uncommon secondary mineral in the zone of oxidation of lead deposits

Where rockhounds find macphersonite

Classic worldwide localities

Moon Anchor mine, Maricopa Co., Arizona, USA
Argentolle mine, near Saint-Prix, Saône-et-Loire, France
Leadhills, Lanarkshire, Scotland
Red Gill mine, Caldbeck Fells, Cumbria, England
Churfürst Ernst mine, Bönkhausen, North Rhine-Westphalia, Germany
Laurium, Greece, in slag

Field-hunting tip

Where it forms: An uncommon secondary mineral in the zone of oxidation of lead deposits. If you start seeing leadhillite, susannite, cerussite in float, you are in the right ground. Typical habit: pseudo hexagonal, tabular. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify macphersonite?+

Mohs hardness is 2.5-3. Luster: adamantine to resinous. The streak is white. Common colors include white, pale amber brown, colorless.

Where is macphersonite found?+

Notable localities include Moon Anchor mine, Maricopa Co., Arizona, USA; Argentolle mine, near Saint-Prix, Saône-et-Loire, France; Leadhills, Lanarkshire, Scotland; Red Gill mine, Caldbeck Fells, Cumbria, England; Churfürst Ernst mine, Bönkhausen, North Rhine-Westphalia, Germany.

Is macphersonite safe to handle?+

Macphersonite contains lead. Contains lead. Wash hands thoroughly after handling specimens and avoid inhaling dust when cleaning or trimming.

What rocks look like macphersonite?+

Macphersonite is most often confused with Leadhillite, Susannite, Cerussite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with macphersonite?+

Macphersonite commonly co-occurs with Leadhillite, Susannite, Cerussite, Caledonite, Pyromorphite, Scotlandite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does macphersonite form in?+

Where it forms: An uncommon secondary mineral in the zone of oxidation of lead deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is macphersonite used for?+

Macphersonite is used in collector.

Find macphersonite on the map

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