Inorganic mercury compounds or mercury salts, more commonly found in nature, include mercuric sulphide (HgS), mercuric oxide (HgO) and mercuric chloride (HgCl2). Most of these are white powders or crystals, except for mercuric sulphide which is red and turns black after exposure to light.
1. Salmon can be kept fresh in your refrigerator for up to two days. As soon as you bring your salmon home, unwrap it and wipe it down with a damp towel then wrap it in plastic wrap and place it in the coldest area of your refrigerator.This is typically the back of the bottom drawer in the refrigerator.. Salmon can be kept fresh in your freezer for up to eight weeks. When you bring home your fresh salmon take it out of the packaging, rinse it off using cold water and pat it dry. Cut your salmon into the desired portions and store it in freezer wrap, foil, freezer bags or an airtight freezer friendly container.
Preferably, the day you buy it from your local fishmonger or grocery store. But sometimes that's not possible. When stored properly in the refrigerator, fresh fish should be cooked within two days, up to three at most, from the time it was purchased. Shelf life does vary from species to species, with some lasting slightly longer. Two days is a good rule of thumb to follow.