Although it does not exhibit classic crystal form which makes the species "corundum" jump out at you, this corundum does have an unusual color zoning, where the periphery is more deeply colored in classic ruby red lipstick outlining around a bright pink center. It is on massive, gemmy, scapolite matrix...the corundum so transparent that the underlying scapolite is easily discernible. This is a fascinating corundum specimen, totally different than any other ruby or sapphire you may own and for me, all the more interesting for that fact. Just blew me away when I saw it and realized what it was.