Object
The objects are two pairs of spectacles from Beamish Museum. They were likely manufactured at the start of the 20th Century.
Pair One: A pair of spectacles made from an alloy of copper, gold, zinc and silver. It has oval shaped lenses which are 38mm x 29mm. The brass frame is thin, ~1mm in diameter, with a flattened wire forming the bridge. The inside of bridge has unidentified hallmarks. The wire rim is held in place by small rivets at the end piece, where the brass wire temple is held in place with a pin. The temple is a thin wire which curves towards the end, to loop around an ear and keep the spectacles in place. Each temple has a small ball of like metal at the end to protect the wearer.
Pair Two: A pince-nez made from an alloy of copper and arsenic. It has circular lenses 40mm in diameter. A thin brass wire forms the bridge which is attached to the lenses by being inserted into a small 1mm hole in the glass. Another 1mm hole is cut into the right lens on the opposite side. A brass pad arm and nose pad of an unidentified material is situated either side of the bridge, attached to the edge of both lenses.
Condition
Spectacles:
- The left lens has been lost
- The right lens is fractured
- The main screw on the right side of the frame has been lost
- The temple arm has become detached
- Evidence of dust and dirt on the surface.
Pince-nez:
- The left lens is fractured and being held together using adhesive tape
- The right lens has several small chips along the top
- Evidence of dust and dirt on the surface.
Conservation
The glass and frames of both spectacles were cleaned using cotton wool swabs with 50:50 ethanol/deionised water in order to remove the loose surface dust and dirt.
Spectacles: The fractured lens was re-adhered using Hxtal NYL-1 epoxy resin adhesive. It was applied directly to the fracture and capillary action drew in the adhesive. The small areas of missing glass from the fractured sections of the lens were filled to increase stability using the same epoxy resin.
A replacement lens was created from clear casting resin. A flat sheet was cast between two melinex sheets which was then heated with a hairdryer and roughly cut using a scalpel. The smooth rounded edges of the lens were achieved by filing the resin using a metal file.
The cast lens was left with a slightly scratched imperfect surface on both sides. This was left for two reasons: the glasses were to have an aged aesthetic, and a smooth lens with a perfect sheen would have also accentuated the fractures on the original lens.
The new lens was positioned in the frames. A steel screw with a 1mm width was cut to length and inserted into the rivet holes within the frames. This was insufficient to hold the frame together and keep the lens in situ so a mixture of Paraloid B72 and glass micro-balloons was applied to provide additional strength to the adhesive. Once set, the white fill was painted with gold acrylic pigment.
Pince-nez: The fractured lens was re-adhered using Hxtal NYL-1. The sherds were secured in their original position using thin strips of masking tape and the epoxy resin was applied to the surface and drawn into the fractures using capillary action.
The chipped edges were filled using the same epoxy adhesive. A silicone rubber mould was created to mimic the rounded edge of the lens, and allowed to cure. Hxtal NYL-1 was applied to the mould using a pipette and allowed to cure in place. Following curing the fill was shaped and smoothed using a combination of mechanical methods.