A mineral is a naturally occuring, homogeneous, solid with a crystalline atomic structure. Crystallinity implies that a mineral has a definite and limited range of composition, and that the composition is expressible as a chemical formula. Some definitions of minerals give them as inorganic materials, however both diamonds and graphite are considered minerals, and both are primarily comprised of carbon, which would make them organic. So this leads me, as an engineer, to believe that mineralogists do not have a good, precise definition of a mineral, but rather a loose definition. The definition above, is the most inclusive and would include all substances currently described as minerals. The key items that make something a mineral are occurring naturally, and the definite crystal structure, that is expressible as a chemical formula. Rocks that do not meet this criteria are referred to as amorphis - not having a definite structure or expressible as a chemical formula. Some elements that occur naturally and are minerals are arsenic, bismuth, platinum, gold, silver, copper, and sulphur.

THE DEFINITION OF ORGANIC: Organic chemistry is the study of those substances containing carbon in combination with hydrogen (H), and a few other non metals, namely oxygen (O), nitrogen (N), sulfur (S) and the halogens (F2, Cl2, Br2, and I2).

Silver ore with 211 Oz/Ton Ag
Native Silver
The Element, Silver, is a heavy metallic element with a brilliant white luster. The chemical symbol for silver, Ag, derives from its Latin name, argentum, meaning "white and shining"--an apt description.

The top photo is of a high grade silver sulfide ore which assayed 211 ounces of silver per ton of ore. The silver is contained in the dark gray areas and the host rock is quartz. The bottom photo is native silver.

The metal has been used as currency since ancient times, both in the mass (bullion) and in the form of coins. Silver shares Group IB of the periodic table with gold and copper. Silver, gold, platinum, and mercury are together categorized as noble metals because they do not oxidize readily when heated, nor do they dissolve in most of the inorganic acids. Because of silver's value it is also categorized as a precious metal, as are gold, platinum, iridium, and palladium. Besides being a monetary metal, silver has also long been used for making jewelry, solid silver or silver-plated objects such as eating utensils. Photography, catalysts, brazing alloys, dental amalgam, bearings and electronics make up the major commercial uses of silver. Photography used to be the primary use of silver, however since the advent of digital and non film based photography, silver's industrial uses now constitute the primary demand for the precious metal, accounting for 40% of silver used, with photography accounting for 22%, and jewelry and silverware makes up for 31% of the silver consumption.