Stilbite

Object/Artifact

-

Crater Rock Museum

Name/Title

Stilbite

Entry/Object ID

2004.1.59

Description

Chemical Composition: (CaNa)3Al5(Al,Si)Si14O40* Crystal System: Monoclinic System Description: Common Name:Stilbite Group Name: Zeolite Chemistry: (CaNa)3Al5(Al,Si)Si14O40*15H2O Location: Wagholi, Pune District, Maharashtra, India Description: Peach colored crystals with white crystals surrounding it. On black matrix. PHYSICAL CHARACTERISTICS: Color is pink or white; also tinted yellow and red. Luster is vitreous to pearly especially on the prominant pinacoid and cleavage surfaces. Transparency: crystals are transparent to mostly translucent. Crystal System is monoclinic; 2/m Crystal Habits include platy often thin crystals that can aggregate together into a wheat sheaflike structure. The prominant pinacoid is sometimes but rarely modified by other pinacoid and prism faces. Cruciform (cross-like) twins can also be found. Also forms radiating nodules. Cleavage is perfect in one direction parallel to the prominant pinacoid. Fracture is uneven. Hardness is 3.5 - 4. Specific Gravity is approximately 2.2 (very light) Streak is white. Associated Minerals are quartz, calcite, babingtonite, apophyllite, heulandite, natrolite and other zeolites. Best Field Indicators are crystal habit, luster, density and associations. Fracture: uneven Hardness: 4 Fluorite Luster: Vitreous Rock Type: Sedimentary Specific Gravity: 2.1-2.2 Streak: white Texture: Crystaline Variety: Stilbite's structure has a typical zeolite openness about it that allows large ions and molecules to reside and actually move around inside the overall framework. The structure contains open channels that allow water and large ions to travel into and out of the crystal structure. The size of these channels controls the size of the molecules or ions and therefore a zeolite like stilbite can act as a chemical sieve. Stilbite's structure contains rings of alumino-silicate tetrahedrons oriented in one direction and this produces the prominant pinacoid faces, the perfect cleavage and the unique luster on those faces.

Collection

Suomynona Mineral Collection, Suomynona Collection

Acquisition

Accession

2004.1

Source or Donor

Suomynona Mineral Collection

Acquisition Method

Donation

Dimensions

Width

6-1/2 in

Depth

4 in

Length

11-5/8 in

Weight

7.13 oz

Dimension Notes

Dimension taken at widest points

Location

Location

Display Case

FS-9

Room

Frieda Smith Hall

Building

Crater Rock Museum

Category

Permanent

Moved By

Ian Cunningham

Date

December 27, 2023