Why is my rock salt black

Black rock salt can have several explanations depending on the context. Here are a few possibilities:

**Purity and Impurities**: Some types of rock salt can contain impurities, which may give them a darker color. These impurities can be from minerals or other natural elements present in the salt deposits.

**Himalayan Black Salt**: If you're referring to black salt used in cooking, it might be Himalayan black salt (kala namak). This salt has a distinctive dark color due to the presence of iron and other minerals, and it has a unique flavor profile.

**Contamination**: If you have rock salt that has turned black, it could be due to contamination from external sources, such as dirt or organic material.

**Oxidation**: If the salt has been exposed to moisture or other environmental factors, it could undergo changes in color due to oxidation or chemical reactions.

**Storage Conditions**: If rock salt is stored improperly or in an environment where it absorbs moisture, it can develop mold or other discoloration.

If you're unsure or if the black color seems unusual for your particular type of salt, it's best to examine it closely or consult with a knowledgeable source.