Hemimorphite

Object/Artifact

-

Crater Rock Museum

Name/Title

Hemimorphite

Entry/Object ID

78.63.41

Description

Chemical Composition: Zn4 Si2 O7 (OH)2 -H2O Crystal System: Hexagonal System Description: Common Name: Botryoidal Hemimorphite Chemistry: Zn4 Si2 O7 (OH)2 -H2O Group: Sorosilicates Location: Chihuahua, Mexico Description: This a large specimen with very diistinct blue hemimorphitic crystals. PHYSICAL CHARACTERISTICS: •Color is blue-green, green, white, colorless, brown and yellow. •Luster is vitreous in large crystals to dull in more compact forms. •Transparency crystals are transparent to translucent. •Crystal System is orthorhombic; mm2 •Crystal Habits include the bladed crystal form and the botryoidal form as the most common. The crystals are usually elongated and flat. The terminations are different at each end. One termination is blunted by a pedion face that is usually bevelled by several dome faces. The other end is pointed, being capped by a pyramid. The other common form is botryoidal producing a grape bunch texture. Often the botryoidal form has a cock's comb appearance showing rough crystal terminations. •Cleavage is perfect in one direction. •Fracture is conchoidal to subconchoidal. •Hardness is slightly less than 5. •Specific Gravity is approximately 3.4+ (above average) •Streak is white. •Associated Minerals include limonite, aurichalcite, calcite and smithsonite. •Other Characteristics: strongly pyroelectric and piezoelectric. •Notable Occurrences include Santa Eulalia and Mapimi, Mexico; New Mexico and New Jersey, USA: England and Zambia. •Best Field Indicators are crystal habit, color, density and luster. Fracture: conchoidal Hardness: 3 Calcite Luster: Vitreous Rock Type: Sedimentary Specific Gravity: 2.7 Streak: white

Collection

Delmar Smith Mineral Collection

Acquisition

Accession

78.63

Source or Donor

Delmar Smith Crystal Collection

Acquisition Method

Donation

Dimensions

Width

4-3/8 in

Depth

1-1/8 in

Length

4-1/8 in

Dimension Notes

Dimension taken at widest points

Location

Location

Container

Left / Back

Drawer

Bottom

Shelf

Right

Cabinet

Case# 31

Wall

East

Building

Freida Smith Hall

Category

Permanent