Eurekadumpite is a rare secondary tellurium mineral typically found as bright yellow coatings or tiny crystalline crusts in oxidized ore zones. It is highly sought after by micromounters and collectors of rare tellurium species due to its scarcity and distinct, vibrant coloration.

Hardness
2.5
Mohs
Luster
Resinous
Streak
Yellow
Transparency
Translucent

Is this eurekadumpite?

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 eurekadumpite with a known reference. Eurekadumpite 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. Eurekadumpite leaves a yellow streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Eurekadumpite typically shows a resinous luster.
  • 4
    Match the color range
    Compare against the expected color range: bright yellow, greenish yellow.
  • 5
    Look at form & habit
    Crystal system: hexagonal. Typical habit: microcrystalline aggregates, crusts, powdery coatings.

Often confused with

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

Often found alongside eurekadumpite

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

All properties

Chemical formula
Cu₄Te₂O₅Cl₂(OH)₆·nH₂O
Mohs hardness
2.5
Density
4.8 g/cm³
Streak
Yellow
Luster
Resinous
Transparency
Translucent
Crystal system
Hexagonal
Crystal habit
Microcrystalline Aggregates, Crusts, Powdery Coatings
Cleavage
None
Rarity
Rare
Uses
Collector
Host rock
Oxidized Tellurium-bearing Hydrothermal Ore Deposits
Typical price
$50-300 per specimen

Where rockhounds find eurekadumpite

Classic worldwide localities

  • Eureka District, Nevada, USA
  • Tombstone, Arizona, USA

Field-hunting tip

Look in oxidized tellurium-bearing hydrothermal ore deposits country — that is the host setting where eurekadumpite typically forms. If you start seeing tellurite, emmonsite, jarosite in float, you are in the right ground. Field specimens usually show a microcrystalline aggregates, crusts, powdery coatings habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify eurekadumpite?+
Mohs hardness is 2.5. It typically shows a resinous luster. The streak is yellow. Common colors include bright yellow, greenish yellow.
Where is eurekadumpite found?+
Notable localities include Eureka District, Nevada, USA; Tombstone, Arizona, USA.
How much is eurekadumpite worth?+
Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.
Is eurekadumpite safe to handle?+
It contains toxic constituents. Contains copper, tellurium, and chlorine. Wash hands thoroughly after handling and avoid inhaling dust or particles. Handle with care, avoid grinding or breathing dust, and store separately.
What rocks look like eurekadumpite?+
Eurekadumpite is most often confused with Tellurite, Emmonsite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with eurekadumpite?+
Eurekadumpite commonly co-occurs with tellurite, emmonsite, jarosite, goethite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does eurekadumpite form in?+
Eurekadumpite typically forms in oxidized tellurium-bearing hydrothermal ore deposits. Working float back to the host body is the standard way to chase a fresh occurrence.
What is eurekadumpite used for?+
Eurekadumpite is used in collector.

Find eurekadumpite on the map

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