Stichtite / Serpentine

Object/Artifact

-

Crater Rock Museum

Stichtite

Stichtite

Name/Title

Stichtite / Serpentine

Entry/Object ID

2009.62.105

Description

Chemical Composition: Hydrated Magnesium Chromi Crystal System: Tetragonal System Description: Common Name: Stichtite / Serpentine Chemistry: Mg6Cr2CO3(OH)16-4H2O, Hydrated Magnesium Chromium Carbonate Hydroxide / (Mg,Fe)3Si2O5(OH)4, Magnesium Iron Silicate Hydroxide Group: Carbonate / Silicate Location: Tasmania, Australia Description: A violet, iridescent layer of crystal on a base of dark and light olive green serpentine. PHYSICAL CHARACTERISTICS OF STICHTITE: Color is a purple-ish rose pink. Luster is waxy or greasy. Transparency: Crystals are translucent. Crystal System is trigonal. Crystal Habits include mostly massive forms that are compact, micaceous or lamellar aggregates. Cleavage is perfect in one direction.. Fracture is uneven to flaky. Hardness is 1.5 - 2 Specific Gravity is approximately 2.1 (well below average) Streak is white to shades of pink or lilac. Associated Minerals are serpentine and chromite. Best Field Indicators are color, habit, locality and associations. PHYSICAL CHARACTERISTICS OF SERPENTINE: Color is olive green, yellow or golden, brown, or black. Luster is greasy, waxy or silky. Transparency crystals are translucent and masses are opaque. Crystal System is variable, see above. Crystal Habits: never in large individual crystals, usually compact masses or fibrous. Veins of viberous serpentine can be found inside of massive serpentine or other rocks. Cleavage the varieties of crysotile have none, in lizardite and antigorite it is good in one direction. Fracture is conchoidal in antigorite and lizardite and splintery in the crysotiles. Hardness is 3 - 4.5 Specific Gravity is 2.2 - 2.6 Streak white Associated Minerals include chromite, olivine, garnets, calcite, biotite and talc. Other Characteristics: serpentine in the rough has a silky feel to the touch and fibers are very flexible. Best Field Indicators softness, color, silky feel and luster, asbestos if present and its flexibility Fracture: uneven to flaky Hardness: 2 Gypsum Luster: Waxy Occurrence: Stichtite is a mineral, a carbonate of chromium and magnesium; formula Mg6Cr2CO3(OH)16·4H2O. Its colour ranges from pink through lilac to a rich purple colour. It is formed as an alteration product from chromium containing serpentine. Rock Type: Sedimentary Specific Gravity: 2.1 Streak: white Variety: Stichtite is a rare and unusual carbonate. It forms in mostly compact masses or micaceous aggregates and is in stark contrast to the majority of carbonates that form well shaped, large and abundant crystals. Its most common locality is near Dundas on the Island of Tasmania and in fact almost all specimens sold in rock shops and from mineral dealers have Dundas listed as the source. Stichtite has a some what dull purple-ish pink to purple-ish rose-red color. Its color, although similar in description to the other rose-red carbonates, it is actually distinctive in its own right when viewed together with the other pink carbonates. Massive green serpentine is usually associated with stichtite and this green and purple-ish pink combination can make for an attractive specimen or an ornamental stone carving.

Collection

RAGM Mineral Collection

Acquisition

Accession

2009.62

Source or Donor

Museum Collection of Minerals

Acquisition Method

Donation

Dimensions

Width

2 in

Depth

2-1/4 in

Length

3-1/4 in

Weight

0.33 oz

Location

Location

Display Case

FS-4-B

Room

Frieda Smith Hall

Building

Crater Rock Museum

Date

January 3, 2024

Location

Container

Right

Drawer

Bottom / Front

Shelf

Right, Right

Wall

South wall

Room

Delmar Smith Hall

Building

Crater Rock Museum

Category

Permanent

Moved By

Steve Miller

Date

January 22, 2010

Location

* Untyped Location

Needs Updated Location - 2022

Category

Permanent

Moved By

Jacob Rier

Date

September 25, 2009

Location

Drawer

2nd from right

Shelf

bottom front right, bottom front right

Wall

South wall

Room

Delmar Smith Hall

Building

Crater Rock Museum

Category

Permanent

Moved By

Jacob Rier

Date

September 25, 2009

Location

Container

Center

Drawer

Top Shelf

Shelf

Left

Cabinet

Case #31

Wall

East

Building

Freida Smith Hall

Category

Permanent