Difficult question’ I use organic chemistry (named as it was thought that all carbon containing compounds were derived from animal or plant sources) as part of my job so carbon is the obvious answer. When I was at school we were taught that carbon had 2 allotropes – graphite and diamond but recently scientists have discovered bucky balls https://en.wikipedia.org/wiki/Buckminsterfullerene
and graphene.https://www.graphenea.com/pages/graphene#.Ykan0hrMKUk
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