Sold Out

salt stalactite - naturally formed salt stalactite - teaching hand specimen

$ 7.50

Back in stock soon. Inquire.

Salt stalactites form annually on a stone causeway between evaporating ponds in the Searles Lake playa. This is the same playa shown with the hanksite collectors on the home page.

Brine splashing onto the rocks during the high evaporative environment of summer drips off to form these stalactites. They completely disappear during the winter, with a new crop forming the following year. These stalactites are useful in the classroom and do not deface natural caves when they are collected.

Searles Lake Minerals extracts a number of salts from the brines of Searles Lake. Most of the brine is pumped from different lakebed surfaces below the playa and is piped to one of three plants, where it  undergoes a series of steps to cause fractional crystallization of various salts. Products of this process are soda ash, borax, anhydrous borax, boric acid and sodium sulfate. Halite is produced from evaporating ponds on the playa surface.

Borax is used in detergents, glass, ceramics and insulation. Anhydrous borax is used in manufacturing heat resistant glass such as Pyrex, in high quality optical and electrical glass, and in enamel glazes.  Borate compounds are also used to prevent rust in radiators’ antifreeze systems, in leather tanning, to correct boron deficiency in plants, as a fire retardant in home insulation and as a bleaching agent for laundry.

Boric acid is used to make textile fiberglass used in tire cords, as an environmentally friendly wood preservative, as a source of boron fibers used in high-strength composites and as an insecticide for roaches. Would you imagine that roach killer was related to the fiberglass cords in your car’s tires?

Anhydrous sodium sulfate has use in the decomposition of wood in the manufacture of paper and cardboard. Soda ash is used to lower the melting temperature of sand in the making of flat glass and mirrors, in the manufacture of aluminum, and for environmental acid controls. Most people would never guess that the brine below the Searles Lake playa would be this useful. The playa and Searles Valley Minerals plants are at Trona, in San Bernardino County, California two mountain ranges and valleys west of Death Valley.

Each photo is one set, either a single stalactite or several. Please let us know which to pack. These are relatively safe for the classroom, but will break if dropped, which is why some are sold in sets - giving you a spare if one is broken. All but the single and the set with four coins have two or more stalactites which have grown together. 


Shipping: in a First Class package unless combined with other items. Click > Shipping < for shipping rates. Use back button to return to this page.

Making multiple purchases? Click on the "combine shipping" button in the shopping cart. We'll send an invoice with combined shipping. A link in that invoice will bring you back to checkout, no hassle.