Former Tamar Union Tin Smelting Works

Former Tamar Union Tin Smelting Works

This is a large tin smelting complex arranged in a U-shaped plan, built primarily of granite rubble walls with brick stacks and a hipped slate roof. The works comprises a single-storey smelting house of double height, a two-storey assay office to the east, and a two-storey unmanufactured tin store and office to the west.

The smelting house dominates the complex. It features an expansive hipped roof which originally supported two large central chimneys, now lost. The west elevation faces onto a cobbled yard and displays a large brick archway with an oval brick opening above, flanked by low buttresses on either side. Square windows, now boarded up, are also present. The south elevation contains a large arched opening with timber doors and three windows on either side, all with elliptical brick arches and timber louvers. This elevation fronts a cobbled yard with an entrance way marked by stone piers and timber gates.

The assay office, positioned at right angles to the east of the smelting house, is a two-storey building with a hipped slate roof. Its west elevation, facing the smelting house, has a 21st-century door with granite quoins on either side, or a window above, both under elliptical arches. The east elevation features stone steps leading up to a 21st-century first-floor entrance door, with two 21st-century eight-over-eight sash windows at first-floor level and two larger 21st-century ground-floor casement windows below, all with elliptical brick arch heads. The south end of the assay office adjoins the east elevation of the smelting house, which displays oval windows above and two arched openings below with granite voussoirs, one now blocked.

The unmanufactured tin store and office occupies the west side of the smelting house at right angles. Its asymmetrical front (east) elevation is accessed by stone steps with an iron railing leading to a first-floor four-panelled door. To either side of the entrance are twelve-pane hornless sash windows with brick arches above. Smaller ground-floor windows flank the steps, featuring segmental arches, internal shutters, and stanchion bars. The building is hipped and has two brick chimneys on its west side and one to the north.

Internally, the smelting house is a full-height open space with an impressive intact timber queen-post roof structure supported by two rows of cast-iron beams, some bearing a date stamp of 1849. The space would originally have contained three furnaces for heating ores to produce tin; these are no longer present but their locations can still be identified by depressions in the floor. In the east corner is a small room forming the corner of the assay house, originally a strong room for storing tin ingots with protective iron bars retained in the windows. This room is now blocked and converted as part of the assay house for use as a bedroom.

The assay house was converted to living accommodation in 2009 with an open-plan first floor and central staircase leading down to two bedrooms and bathroom below. Most internal decoration is modern, though doorway and window openings which originally connected to the smelting house survive, albeit blocked. The building retains a timber king-post roof.

The unmanufactured tin store and office spans two floors. The ground-floor store room is a long open space accessed via a timber plank door in the south-west corner of the smelting house. The first-floor office is largely late-19th century in character. The king-post roof is intact, and a section of lath and plaster ceiling survives at the north end. An internal lath and plaster division wall survives at the south end. The north end is now largely open with some fragments of internal lath and plaster wall remaining, together with a chimney breast.