The NIST Materials Data Curation System (MDCS) provides a means for capturing, sharing, and transforming materials data into a structured format that is XML based amenable to transformation to other formats. The data are organized using user-selected templates encoded in XML Schema. These templates are used to create data entry forms. The documents are saved in a non-relational (NoSQL) database, namely MongoDB. The data can be searched and retrieved via several means: by a template-driven web-based form, by a SPARQL endpoint query, and by a RESTful API call. The system also enables the interconnection of MDCS repositories for federated searches.