Adamite

Object/Artifact

-

Crater Rock Museum

Name/Title

Adamite

Entry/Object ID

78.62.96

Description

Chemical Composition: Zn2AsO4(OH) Crystal System: Orthorhombic System Description: Common Name: Adamite Chemistry: Zn2AsO4(OH) Group Name: Arsenates Location: Durango, Mexico Description: Delmar described this specimen as a piece of Adamite (Hydrous Zinc Arsenate) from Durango,Mexico. Colors: Ochre Iron base has olive and light green and little white Adamite crystals. PHYSICAL CHARACTERISTICS: Color is typically green due to trace amounts copper and or uranium, yellow, rarely white and occasionally purple due to trace amount of cobalt. • Luster is adamantine. • Transparency: Crystals are transparent to translucent. • Crystal System is orthorhombic; 2/m 2/m 2/m • Crystal Habits include diamond shaped, wedge-like prisms sometimes modified with minor prismatic faces and terminated by a double triangle. Mostly in druses and radiating clusters that can form wheel and wheat sheaf shapes. Rarely in a perfectly smooth botryoidal habit like smithsonite, but commonly found with well formed double triangular crystal terminations that sparkle on the top of the "sub" botryoidal surface. • Cleavage is perfect in two directions at non-right angles to each other (domal). • Fracture is conchoidal. • Hardness is 3.5. • Specific Gravity is approximately 4.4 (heavy for translucent minerals) • Streak is white to pale green. • Other Characteristics: Strongly fluoresces green in short and long UV light. • Associated Minerals are legrandite, limonite, smithsonite, austinite, paradamite, aragonite, calcite, mimetite, conichalcite and other oxidation zone minerals. • Notable Occurrences include the famous mines at Mapimi, Mexico; also Greece and California and Utah, USA. • Best Field Indicators are crystal habit, color, luster, density, fluorescences and associations. Fluorscent

Collection

Delmar Smith Mineral Collection

Acquisition

Accession

78.62. 96

Dimensions

Width

2-1/2 in

Depth

1-1/2 in

Length

2 in

Dimension Notes

Dimension taken at widest points

Location

Location

Display Case

FS-9

Room

Frieda Smith Hall

Building

Crater Rock Museum

Category

Permanent