Rhodonite

Object/Artifact

-

Crater Rock Museum

Name/Title

Rhodonite

Entry/Object ID

2013.1.23

Description

Chemical Composition: SiO2 Crystal System: Triclinic System Description: Common Name: Rhodonite Chemistry: (Mn2+,Fe2+,Mg,Ca)SiO3 Group: Silicates Location: Minas Geris, Brazil Description: This is a small rectangular slab. It has been polished on one side. The colors are pink and green Physical Charateristics: Rhodonite is a manganese inosilicate, (Mn, Fe, Mg, Ca)SiO3 and member of the pyroxenoid group of minerals, crystallizing in the triclinic system. It commonly occurs as cleavable to compact masses with a rose-red color (the name comes from the Greek ??d?? rhodos, rosy), often tending to brown because of surface oxidation. Rhodonite crystals often have a thick tabular habit, but are rare. It has a perfect, prismatic cleavage, almost at right angles. The hardness is 5.5–6.5, and the specific gravity 3.4–3.7; luster is vitreous, being less frequently pearly on cleavage surfaces. The manganese is often partly replaced by iron, magnesium, calcium, and sometimes zinc which may sometimes be present in considerable amounts; a greyish-brown variety containing as much as 20% of calcium oxide is called bustamite; fowlerite is a zinciferous variety containing 7% of zinc oxide. Fracture: Conchoidal Hardness: 7 Quartz Luster: Pearly Rock Type: Sedimentary Specific Gravity: 2.68-2.72 Streak: White

Collection

RAGM Mineral Collection

Acquisition

Accession

2013.1

Source or Donor

Crater Rock Museum (Misc. donors)

Acquisition Method

Gift

Dimensions

Width

3-1/2 in

Depth

7/8 in

Length

4-1/2 in

Location

Location

Drawer

Bottom Shelf

Shelf

Left

Cabinet

Case# 33

Wall

East

Building

Freida Smith Hall

Category

Permanent