A few years later, additional material was obtained from the type locality of Messel and studied with optical and x-ray methods. The specimen was determined to consist primarily of material identical to the neomesselite described by Frondel with a rim of anapaite. Since it is likely that the mixture studied by Muthmann was primarily this mineral, it was decided around 1959 that the name neomesselite should be discarded in favor of messelite.[9] When the IMA was founded, messelite was grandfathered as a valid mineral species.[3]