Nickelpicromerite is a rare secondary sulfate mineral occurring as efflorescences or crusts in the oxidized zones of nickel-rich ore deposits. It is best identified by its vibrant green color and association with other nickel sulfates in mine workings. Collectors typically seek out well-formed micro-specimens from historic European mining districts.

Hardness

2.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrarePicromerite Group family

Nickelpicromerite

Hardness: 2.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this nickelpicromerite?

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 nickelpicromerite with a known reference. Nickelpicromerite sits at Mohs 2.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Nickelpicromerite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Nickelpicromerite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: green, yellow-green.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: crusts, granular, prismatic crystals.

Often confused with

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

Often found alongside nickelpicromerite

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

All properties

Chemical formula: (K,Ni)₂Mg(SO₄)₂·6H₂O
Mohs hardness: 2.5
Density: 2.14 g/cm³
Colors: Green Yellow-green
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Crusts, Granular, Prismatic Crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Secondary Mineral in Mine Dumps and Oxidized Zones
Typical price: $20-100 thumbnail

Where rockhounds find nickelpicromerite

Classic worldwide localities

Schneeberg, Saxony, Germany
Jachymov, Czech Republic
Lavrion, Greece
Broken Hill, Australia

Field-hunting tip

Look in secondary mineral in mine dumps and oxidized zones country, the host setting where nickelpicromerite typically forms. If you start seeing retgersite, morenosite, epsomite in float, you are in the right ground. Field specimens usually show a crusts, granular, prismatic crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify nickelpicromerite?+

Mohs hardness is 2.5. It typically shows a vitreous luster. The streak is white. Common colors include green, yellow-green.

Where is nickelpicromerite found?+

Notable localities include Schneeberg, Saxony, Germany; Jachymov, Czech Republic; Lavrion, Greece; Broken Hill, Australia.

How much is nickelpicromerite worth?+

Typical asking prices fall in the range of $20-100 thumbnail. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like nickelpicromerite?+

Nickelpicromerite is most often confused with Picromerite, Goslarite, Melanterite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with nickelpicromerite?+

Nickelpicromerite commonly co-occurs with Retgersite, Morenosite, Epsomite, Gypsum. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does nickelpicromerite form in?+

Nickelpicromerite typically forms in secondary mineral in mine dumps and oxidized zones. Working float back to the host body is the standard way to chase a fresh occurrence.

What is nickelpicromerite used for?+

Nickelpicromerite is used in collector.

Find nickelpicromerite on the map

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