The Evaporites ©2010 Dr. B. C. Paul Acknowledgement is given to Industrial Minerals SME, Nevada-outback- gems.com, mindat.org, minerals information institute,

Sources of Salt and Evaporite Deposits From Evaporites By John K. Warren

Relationship of Temperature and Continental Position to Evaporite Deposits From Evaporites By John K. Warren

Borax Na 2 [B 4 O 7 ] · 10H 2 O S.G Hardness 2 - 2½ Color Colorless, grey, white, yellowish, seldom bluish or greenish; colorless in transmitted light. Fluorescence – not fluorescent Boron 11.3% B 2 O %

Colemenite Ca 2 B 6 O 11 ·5(H 2 O) S.G Hardness 4.5 Color Colorless, Gray, Gray white, Yellowish white, White. Fluorescence Not Fluorescent Boron 15.78% B 2 O %

Tincalconite Na 6 [B 4 O 5 (OH) 4 ] 3 ·8(H 2 O) S.G Hardness 2 Color White Fluorescence – not fluorescent Boron 15.16% B 2 O %

Kernite Na 2 B 4 O 6 (OH) 2 ·3(H 2 O) S.G , Average = 1.91 Hardness Color Colorless, White. Fluorescence – None Boron 14.9% B 2 O %

Ulexite NaCaB 5 O 6 (OH) 6 ·5(H 2 O) S.G , Average = 1.95 Hardness 2.5 Color Colorless, White. Fluorescence None Boron 13.34% B 2 O %

Boron Minerals Come from old evaporite deposits Used as a flux in metals and ceramics Important in making fiberglass insulation Used in Boro-Silicate Glass and in enamals In Soaps and Detergents

Boron Uses

Boron Processing Most Boron mined by open pit Ore is crushed and then dissolved –Crystalized under a vaccuum and dried –Resulting Anyhydrous borax is then used for boric acid Some minerals can be used directly in boric acid production Others can be used directly in making fiberglass

Boron Production and Reserves

What is Boron Worth? Around 50 cents per pound.

A Common Evaporite Halite NaCl S.G Hardness 2 - 2½ Color Colorless, white, red, yellow, orange, pink, green, blue, violet, gray

Salt Uses

Chlorine Made by electrolysis of dissolved salt Chlorine needed in many petroleum based plastics and synthetics –Example Polyvinalchloride (PVC) Needed in Elastic products Used in water purification applications Used in fuel additives and solvents

Sodium Sodium Hydroxide (caustic) –Byproduct of chlorine production –Needed to making Cellophane and Nylon –Key to paper making –Supplies generally constrained by chlorine production As an alkaline agent or for making –Sodium Bicarbonate, Sodium cyanide, sodium nitrate, sodium silicate may want to start with other minerals

Salt Production Reserves are considered inexhaustible

What is Salt Worth? Around 1.5 to 2 cents per pound

Potash Potassium a key nutrient in plant growth –One of 3 K, N, P Source from evaporite deposits Brine sources are selectively precipitated to bring down potassium salts separate from others For solid sources the rock is ground and then separated by using flotation or small density differences for heavy media –There is also an electric charging process that allows the ore to be processed dry

Sylvite KCl S.G Hardness 2.5 Color White, Yellowish white, Reddish white, Bluish white, Brownish white. Fluorescence – None Potassium 52.45%

Langbeinite K 2 Mg 2 (SO 4 ) 3 S.G Hardness Color Colorless, Violet, Greenish, Gray, Yellowish. Fluorescence – Yes Potassium 18.84%

Uses of Potash

Production and Reserves Reserve base is Unusually large Compared to Production.

What is Potash Worth? Around 10 cents Per pound of K 2 O

Specialized Evaporites Trona Na 3 (CO 3 )(HCO 3 )·2(H 2 O) S.G , Average = 2.13 Hardness 2.5 Color Colorless, Gray white, Grayish, Yellowish, Yellowish white. Fluorescence None

Mirabilite and Thenardite Mirabilite Na 2 SO 4 ·10(H 2 O) S.G Hardness Color Colorless, White, Yellowish white, Greenish white. Fluorescence None Thenardite Na2SO4 S.G , Average = 2.68 Hardness 2.5 Color White, Grayish white, Yellowish white, Reddish white, Brownish white. Fluorescence - Yes

Locations for Deposits Most of World Reserves

Production and Resources

What is Trona Used for?

What is it Worth? Around 5 Cents a pound