The assayer’s house is one of the largest and most eye-catching buildings in the Liquation Works. Two storeys high, it comprises a main building and a side building to the north-west. Both buildings have two storeys; each has a gabled roof featuring a range of dormer designs. While the ground floors of the buildings are solid stonework, the upper floors and the gables are half-timbered. When the Assayer’s house and the adjoining copper depository were remodelled, the adjacent building ‒ which has an oriel window and round windows on the ground floor ‒ was erected with older materials from the former copper depository. This was where the refined copper intended for sale was originally stored. The Assayer’s house and the copper depository date back to around 1586.