Records of environmental samples, such as minerals, soil, rocks, water, air and plants, are distributed across legacy databases, spreadsheets or other proprietary data systems. Sharing and integration of the sample records across the Web requires globally unique identifiers. These identifiers are essential in order to locate samples unambiguously and to manage their associated metadata and data systematically. The International Geo Sample Number (IGSN) is a persistent, globally unique label for identifying environmental samples. IGSN can be resolved to a digital representation of the sample trough the Handle system. IGSN names are registered by end-users through allocating agents, which are the institutions acting on behalf of the IGSN registration agency. As an IGSN allocating agent, we have implemented a web service based on existing open source tools to streamline the processes of registering IGSNs and for managing and disseminating sample metadata. In this paper we present the design and development of the web service and its database model for capturing various aspects of environmental samples. Previous work by the System for Earth Sample Registration (SESAR) was aimed primarily at individual investigators, whereas our work focuses on curating sample descriptions from larger collaborative projects. The paper describes the linkage between the IGSN metadata elements and the sampling concepts specified in existing common data standards, e.g., the Open Geospatial Consortium (OGC) Observations and Measurements standard. This mapping allows the application of the IGSN model across different science domains. In addition, we show how existing controlled vocabularies are incorporated into the service development to support the metadata registration of different types of samples. The proposed sample registration and curating approach has been trialled in the context of the Capricorn Distal Footprints project on a range of different sample types, varying from water to hard rock samples. The observed results demonstrate the effectiveness of the service while maintaining the flexibility to adapt to various media types, which is critical in the context of a multi-disciplinary project.