Borax

Object/Artifact

-

Crater Rock Museum

Name/Title

Borax

Entry/Object ID

2009.62.71

Description

Chemical Composition: Na2B4O7 -10H2O Crystal System: Orthorhombic System Description: Common Name: Borax Chemistry: Na2B4O7 -10H2O, Hydrated sodium borate. Group: Carbonates Location: Borax-Boron, CA, USA Desription: Translucent soft white pyramidal crystals grouped tightly together. PHYSICAL CHARACTERISTICS: Color is white to clear. Luster is vitreous. Transparency crystals are transparent to translucent. Crystal System is monoclinic; 2/m Crystal Habits include the blocky to prismatic crystals with a nearly square cross section. Also massive and as crusts. Cleavage is perfect in one direction. Fracture is conchoidal. Hardness is 2 - 2.5 Specific Gravity is approximately 1.7 (very light) Streak is white. Associated Minerals are calcite, halite, hanksite, colemanite, ulexite and other borates. Other Characteristics: a sweet alkaline taste, alters to chalky white tincalconite with dehydration. Best Field Indicators are crystal habit, color, associations, locality, density and hardness. Fracture: conchoidal Hardness: 3 Calcite Luster: Vitreous Occurrence: Borax is a complex borate mineral that is found in playa lakes and other evaporite deposits. Rock Type: Sedimentary Specific Gravity: 2.2 Streak: white Variety: Borax is directly deposited in arid regions from the evaporation of water in intermittent lakes called playas. The playas form only during rainy seasons due to runoff from adjacent mountains. The runoff is rich in the element boron and is highly concentrated by evaporation in the arid climate. Eventually the concentration is so great that crystals of borax and other boron minerals form.

Collection

RAGM Mineral Collection

Acquisition

Accession

2009.62

Source or Donor

Museum Collection of Minerals

Acquisition Method

Donation

Dimensions

Height

2 in

Width

2-3/4 in

Length

6-1/2 in

Weight

21.58 oz

Dimension Notes

Dimension taken at widest points

Location

Location

* Untyped Location

RD-4

Category

Permanent

Moved By

Curtis Gardner

Date

May 24, 2023

Notes

Added current location

Location

Container

Right

Drawer

Top

Shelf

Right, Right

Wall

South wall

Room

Delmar Smith Hall

Building

Crater Rock Museum

Category

Permanent

Moved By

Steve Miller

Date

January 15, 2010

Location

Container

Right

Drawer

Top

Shelf

Right, Right

Wall

South wall

Room

Delmar Smith Hall

Building

Crater Rock Museum

Category

Permanent

Moved By

Steve Miller

Date

January 15, 2010