Black Spinel, Rhodium over Sterling Silver Cross Pendant on 18" 925 chain

Black Spinel, Rhodium over Sterling Silver Cross Pendant on a 18" 925 chain Measurements are in the photos In good pre-owned condition with minimal signs of ware Please view all photos thoroughly as they are part of the description and to show condition I'm happy to answer any questions you may have and Happy to add any additional photos, if needed. Thank you! Rhodium is one of the rarest metals found in the earth. At only .00002 parts per million in the Earth's crust. There are 25 radioactive isotopes of rhodium and 18 of the isotopes have half lives of less than 1 hour.Rhodium has only 1 electron on its outer shell unlike the other group 9 metals.Rhodium is extremely hard to take out from the ores that contains it. Rhodium is part of the group called Platinum Group Metal(PMG). There is also black rhodium.