Abstract: The present invention is directed to synthetic bactericidal compositions having clay like properties and a method of using these compositions to topically treat bactenally-caused skin infections and skin diseases. The compositions within the scope of the invention compnse a bactericidal effective amount of a reducing agent, such as py?te, marcasite, pyrrhotite, FeS2, FeS, FeS04—or other reducing agents having like properties, and a natural clay or clay mineral and/or synthetic clay or clay mineral, or other suitable matenals having clay-like properties. The synthetic bactericidal compositions are synthesized by adding the reducing agent to the clay or clay mineral. It is the presence of the reducing agent in said compositions that renders them bacte?cidal.

Abstract: A method of quantitatively determining surface area of a sample uses polyvinylpyrrolidone (PVP) dispersed in a solution containing the sample, and determining the amount of PVP that has deposited on the sample.

Abstract: A method is provided for the manufacture of mineral power crystals having a uniform mean size. The method includes forming a solution which is highly supersaturated with respect to the crystals. The crystals of the solution are Ostwald ripened at a level of supersaturation that produces an Ostwald steady state crystal size distribution shape wherein the crystals are of a uniform size. After Ostwald ripening ceases, the crystals further grow by supply controlled growth which uniformly increases the size thereof. This enables the supply controlled growth to be terminated at a selected, controlled point so as to produce a desired mean crystal size.