Yttrogummite is an yttrium-bearing variety of gummite mineral. It is a rare earth mineral containing relatively large amounts of the yttrium earths. It is an alteration product of yttrian uraninite.Yttrogummite on Mindat.org
It was first described by Adolf Erik Nordenskiöld in 1878, from the Garta Feldspar quarry in Arendal, Norway.
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