All excavated crucible fragments were visually examined on site. No complete crucibles were unearthed. Based on their visual appearance, the fragments were divided into lids, walls, and bases. The examination concluded that the fragments were from a single type of lidded crucible, which sat on a (so-called) pad.

All lid fragments are flat ceramic disks c. 8 cm in diameter with a thickness ranging from 0.5 to 1 cm and they have a central hole 1 cm in diameter, slightly raised proud on one side.  There are impressions of parallel lines, on the underside of the lid. Around the exterior circumference there remains evidence of an applied ring of clay, luting, which attached the lid to the crucible wall.

The crucible wall became thinner and darker the closer it was to the lid. The colour and thickness changes from white and c. 1 cm in thickness, at the lower part of the wall near the base, to dark grey and c. 0.5 cm, at the upper part of the crucible where it meets the lid.  Another feature on the exterior side of all the wall and base fragments was a shiny black glaze, occasionally with reddish lines and undulating (wavy) pattern. The black glaze is thinner, c. 0.1 cm on the upper parts of the wall, and thicker, c. 0.5 cm towards the pad. These features are assumed to change uniformly along the height of the crucible.

There are rust coloured encrustations on the underside of some lids, and on the interior side of the upper walls of the crucible. These were identified as partially corroded steel prills. Below these rusty encrustations, towards the base, is a glassy green ring identified as slag.  The location of the glassy green fin averages around 8 - 10 cm high from the base measured at the inside of the crucible. 

The internal profile of the lower part of the wall to the base, below the glassy green slag, is hemispherical with a thin layer of a dark green vitreous slag, which sometimes has a honey-combed pattern or is comparatively smooth. The interior diameter of the bases varies from c. 6 cm to c. 6.5 cm, although the external diameter is consistently c. 8 cm.  The crucible bases have an external bottom profile that is either flat or slightly arched, probably due to being placed on to the pad while still in a comparatively malleable state.  The base of the crucible has a disk shaped attachment, a (so-called) pad, made of a different ceramic fabric. The diameter of the pad is c. 8 cm and it has a thickness of typically between 1 and 2 cm. Pieces of broken crucibles, c. 1 cm² and 0.5 cm thick are attached to the pad’s perimeter by a black glaze.  These are labeled “refractory mass” and are interpreted as part of the furnace floor (see Furnaces).

By observing the rate at which the wall features apparently changed from the base to the lid, the height of the crucibles is estimated at between 18 and 20 cm. The lid, wall and base fragments all indicate that the shape of the crucible was a flat-bottomed cylinder with an external diameter of c. 8 cm and an average internal diameter of about 7 cm at the top and 6 cm at the bottom.