Blockchain technology has gained popularity as a decentralized, tamper-proof, and verifiable data structure. Apart from financial transactions and assets management, there is also a growing interest in using it as a backbone for metadata management systems. Metadata systems aim to facilitate the organization of big data and to provide a comprehensive interface to users for data discovery and navigation. However, the fundamental design of the blockchain has the limitations in data querying and visualization that results in poor user experience. On the other side, the graph databases are widely adapted for building user friendly metadata systems with efficient relationship discovery capabilities. In our paper, we attempt to preserve the benefits of both types of systems through the integration of blockchain and property graph technologies. First, we formalize the structures used for metadata storage and a metadata conceptual model. Second, we provide the algorithms for mapping the (meta)data from the blockchain to the property graph model. And third, we show a prototype implementation of the integrated system to validate our proposal.