Paper conservation
Foxing, acid burn, old tape and cockling — what a paper conservator can reverse on a drawing or watercolour, and what nobody can.
Paper damage is mostly framing damage. Works on paper spend decades sealed against acidic board, behind glass that admits ultraviolet, in rooms that are humid in winter — and the marks that result are so common they have their own vocabulary. A good proportion of it is genuinely reversible, at a cost that is modest beside painting conservation.
What can be put right
Foxing and mould staining
The rust-coloured speckling that appears across old sheets, caused by a combination of humidity, impurities in the paper and fungal growth. It is reduced or removed by washing and controlled bleaching, and the result on a badly foxed sheet can be startling. It is also the damage most likely to return if the work goes back into the same frame in the same room.
Acid burn and mount burn
The brown line exactly where the window mount sat, and the overall warm tone of a sheet backed onto wood pulp board. Acid migrates out of cheap framing materials into the paper and keeps going. Washing and deacidification arrest it and lift much of the discolouration, and reframing to conservation standard is what stops it recurring.
Tape, hinges and old adhesive
Masking tape, brown gummed tape and self-adhesive tape applied at some point in the last fifty years, now brown, brittle and staining through to the front. Removal is delicate, solvent work and is bread-and-butter for a paper conservator. Never attempt this one at home — pulling old tape off a sheet takes the surface with it.
Cockling, creases and tears
Rippling from damp or from being stretched against a mount, handling creases through the sheet, and tears at the edges. Paper is humidified and flattened under weight over days rather than pressed, and tears are repaired from the back with Japanese tissue and wheat starch paste, which is both strong and reversible.
What cannot be undone
Fading is permanent. Light damage is the one thing no conservator can undo — a watercolour that has hung opposite a window for thirty years has lost pigment, and washing the paper only makes the loss more obvious against a cleaner ground. A trimmed sheet cannot be made whole again. And washing removes some of the sheet's own history along with the dirt, which on an early or important work is a real argument for doing less rather than more.
Is it worth doing?
More often than for paintings, because the work is comparatively cheap and the improvement is visible. The exception is a sheet of modest value: full conservation on a decorative watercolour can cost more than the watercolour, and reframing it properly to stop the damage getting worse is frequently the better answer.
The work is carried out by a conservation studio we work with, not in-house, and the cost is quoted before anything begins. How restoration works here sets out the whole of that arrangement. If you do not yet know what the work is, a valuation comes first and costs nothing — it is the thing that decides whether any of this is worth spending.