A version of the Materials Data Vocabulary structured as Simple Knowledge Organization System (SKOS). The XML was originally created by the TemaTres software. This vocabulary describes the applicability to material science of records in the NIST Materials Resource Registry (NMRR - https://materials.registry.nist.gov/). The NMRR allows for the registration of materials resources, bridging the gap between existing resources and the end users. The NMRR functions as a node in a federated system, making the registered information available for research to the materials community. This is being developed at the National Institute of Standards and Technology and is made available to solicit comments from the Material Science community. (An Excel version of the file is also included in the distributions for ease of use.)