THENARDITE
Specimen thn-4

Dims: 2.4 x 1.9 x 1.5" (6.0 x 4.8 x 3.9 cm)

Wt: 2.3 oz. (65 g)

Searles Lake, Trona, San Bernardino County, California, U.S.A.

A pale pink Thenardite crust coats the halite base of this hand specimen. The Thenardite is massive, showing no evidence of crystal form, and has a pink color that is paler than that of the halite base. Its luster is essentially dull, and it is translucent or opaque. As it has pseudomorphed from the halite below, it has retained the original shape, including the "hopper effect" of the halite- the halite itself still has very good form.

Dims: 1.5 x 1.3 x 0.8" (3.8 x 3.2 x 2.0 cm)

Wt: 14 g

Soda Lake, Carrizo Plain, San Luis Obispo County, California, U.S.A.

At least 6 tabular Thenardite crystals are clustered together to make up this small hand specimen. The largest of these crystals has dimensions of 1.0 x 1.0 x 0.4" (2.6 x 2.6 x 1.0 cm), and all appear to be in excellent condition, showing no fresh damage. Their orthorhombic form is quite good, and all have a dull, pale gray color and a waxy luster. They are only dimly transparent at best. A white, powdery substance- likely a decomposition product- coats the less-exposed areas on the cluster, and no base or host material is present.

Dims: 2.6 x 2.2 x 1.4" (6.7 x 5.7 x 3.5 cm)

Wt: 1.7 oz. (47 g)

Soda Lake, San Luis Obispo County, California, U.S.A.

At least 30 intergrown Thenardite blades are clustered together to form this hand specimen. These blades reach dimensions of 1.3 x 1.0 x 0.4" (3.2 x 2.6 x 1.0 cm) and are generally in excellent condition, showing almost no damage. Their orthorhombic form is very good, given their intergrowth. All have a dark gray color and a pearly-to-waxy luster, and are translucent to dimly transparent along their edges. There is no host rock present.

Dims: 2.0 x 1.9 x 1.5" (5.1 x 4.7 x 3.7 cm)

Wt: 2.0 oz. (57 g)

Soda Lake, San Luis Obispo County, California, U.S.A.

A cluster of at least 10 intersecting Thenardite tablets makes up this small cabinet specimen. These blades reach dimensions of 1.4 x 1.1 x 0.8" (3.7 x 2.8 x 2.1 cm) and are in excellent condition, showing very little damage. All have excellent orthorhombic bladed form. All are colorless but contain numerous black and gray inclusions, making them appear essentially black, and their luster is waxy. There is no host rock present.

Dims: 2.6 x 1.7 x 1.0" (6.7 x 4.4 x 2.6 cm)

Wt: 1.3 oz. (38 g)

Soda Lake, San Luis Obispo County, California, U.S.A.

This cluster of Thenardite tablets is in very good condition, though it shows some weathering at one end. It contains tetragonal tabular crystals that reach dimensions of 0.8 x 0.5 x 0.2" (2.0 x 1.2 x 0.5 cm). They have a gray-black color due to intense inclusion and a waxy luster, and show dim transparence along their edges. There is no host rock present.

Dims: 2.8 x 2.3 x 2.2" (7.2 x 5.8 x 5.5 cm)

Wt: 4.3 oz. (117 g)

Soda Lake, San Luis Obispo County, California, U.S.A.

This large Thenardite cluster contains at least 10 tabular crystals, all of which are in excellent condition. The largest of these has dimensions of 2.2 x 1.4 x 0.5" (5.5 x 3.6 x 1.2 cm). All have excellent orthorhombic form, though the largest crystals are a bit rougher than the smaller ones. They have a gray-black color that is caused by intensely concentrated inclusions, but all are moderately transparent around their edges. There is no host rock present.