Of the blue minerals, azurite is likely the best known and, when in extraordinary specimens, is certainly one of the most desirable and expensive. What better compliment, therefore, for a mineral than to be often confused with azurite. Such is the case with the much-rarer linarite, a striking blue mineral that occurs, like azurite, in the oxidized parts of base-metal ore deposits, most frequently in arid and semiarid terrain. In more than one instance it was discovered, all too late, ...