Hemimorphite

Object/Artifact

Crater Rock Museum

Hemimorphite

Name/Title

Hemimorphite

Entry/Object ID

2014.1.62

Description

Chemical Composition: Al(OH)3 Crystal System: Hexagonal System Description: Common Name: Hemimorphite Chemistry: Zn4 Si2 O7 (OH)2 -H2O, Group: Silicates Location: New Mexico Description: Small specimen with a light green botroydial crystals in the cavities. Physical Charateristics: Color is a bright emerald green or dark green to almost black. • Luster is vitreous to pearly on cleavage surfaces. • Transparency: Crystals are transparent to translucent. • Crystal System is monoclinic; 2/m. • Crystal Habits include acicular or fibrous crystals aggregated into coatings and tufts as well as small tabular crystals and reniform, massive or granular specimens. Terminations tend to be rounded or dome-like. Twinning is common and gives an orthorhombic look to larger crystals Cleavage is perfect in one direction nearly perpendicular to length. • Fracture is uneven. • Hardness is 3.5 - 4 • Specific Gravity is approximately 3.9+ (above average for translucent minerals) • Streak is green. • Other Characteristics: Does not effervesce in hydrochloric acid. • Associated Minerals are limonite, cuprite, chrysocolla, cyanotrichite, malachite, langite, posnjakiteand azurite. • Notable Occurrences include numerous locations in Chile; Ural Mountains, Russia; England; Italy; Romania; Zaire and several locations in Arizona, Nevada, California, New Mexico and Utah, USA. • Best Field Indicators are crystal habit, associations, hardness, cleavage, non-reaction to hydrochloric acid and color. Hardness: 7 Quartz Rock Type: Sedimentary

Collection

RAGM Mineral Collection

Acquisition

Accession

2014.1

Source or Donor

Crater Rock Museum (unknown donors)

Acquisition Method

Gift

Dimensions

Height

3 in

Width

1-3/4 in

Length

2-1/4 in

Location

Display Case

FS-11

Room

Frieda Smith Hall

Building

Crater Rock Museum

Date

July 22, 2023