[Chemical composition] Na 39.4%, Cl 60.6%. Often contains brine, air bubbles, mud and organic wraps. Gypsum , KCl, MgCl 2, etc. are sometimes wrapped.
[Form] Isometric crystal system. It is often in the form of a cube, and a funnel-like step depression is common on the crystal face. The aggregate is in the form of a dense block, a granular shape, a plate shape, and the like.
[Physical properties] colorless or white, but often due to impurities and gray (argillaceous dots), yellow (hydrogen-containing iron oxide), red (anhydrous containing less water iron oxide), brown and black ( Contains organic matter, etc. The blue stone salt is due to the free sodium ions in the structure. Glass luster, greased after weathering. Hardness 2-2.5. Crisp. Cube cleavage is complete. The proportion is 2.1-2.2. soluble in water. It has a salty taste. The burning flame is yellow (the reaction of Na).
[Formation and production] Stone salts are mainly formed with exogenous deposits, and their occurrences are as follows:
(1) Coastal lagoon sedimentation - sea salt.
(2) Inland lake sediments - pool salt or lake salt.
(3) Dissolve and infiltrate into brine - well salt.
(4) Rock salt formed by the ancient continental climate.
[Identification characteristics] It is characterized by small hardness, easy dissolution, salty taste, and cube cleavage. The flame is yellow when burning.Ningbo River Islet Kayak Co., Ltd , http://www.islet-kayak.xyz