Rhenium: Last Naturally Occurring Stable Precious Metal Discovered
In the periodic table of elements, rhenium is found as a third-row transition metal in group 7. Known to be one of the rarest precious metals in the Earth's crust, rhenium has an average concentration of 1 part per billion. It is obtained mainly as a by-product of the refinement of two other chemical elements - copper and molybdenum.
Largest Gold Nuggets Discovered: Welcome Stranger And Hand Of Faith
Gold nuggets are naturally occurring large masses of native gold found in alluvial deposits. Often they are concentrated by watercourses and recovered by placer mining. In other instances, gold nuggets are found in piles of residue in sites where mining operations once took place.
Safety Issues Concerning Precious Metals
The metallic chemical elements collectively known as precious metals are called as such because of their extreme rarity and high economic value. Precious metals occur naturally or are by-products of the processing of other less rare metals.