To derive is defined as to come from, be created from or be developed out of something else. An example of derive is when you get the idea for a new fund raising event based on the event the previous year.
Rubidium: geological information. Rubidium is far too reactive to be found as the free metal in nature. It is relatively rare, although it is the 16th most abundant element in the earth's crust. Rubidium is present in some minerals found in North America, South Africa, Russia, and Canada. It is found in some potassium minerals (lepidolites, biotites, feldspar, carnallite), sometimes with caesium as well.
Iridium is a chemical element with symbol Ir and atomic number 77.  It is a very hard, brittle, silvery-white transition metal of the  platinum family.2 people found this useful. Edit.ridium was discovered in 1803 among insoluble impurities in natural platinum. Smithson Tennant, the primary discoverer, named the iridium for the goddess Iris, personificatio â¦ n of the rainbow, because of the striking and diverse colors of its salts.