Small bronzes housed indoors have an easy time of it compared to their large companions outdoors in the public arena. They are sheltered from the urban air and ever-changing weather, but their environment still has an impact on them and if you want to keep your small bronzes as stable as possible then consider these 10 tips.
1: Dust Regularly – Don’t be frightened of touching a bronze just because it’s an artwork. If you use a dry micro-fibre cloth or a soft bristle brush you’ll be doing a lot of good rather than harm. Removing dirt and grime prevents prevents reactions between the pollutants in dust and the metal’s surface. We all hate more housework, but it will avoid the start of pockets of localised corrosion happening over time. Prevention is always better than cure.
2: At least once a year, give the statue a thorough clean and apply some wax. Putting a barrier layer in place is one of the best ways of protecting a bronze’s surface. Outdoor pollutants from traffic and the outdoor such as nitrogen oxides, sulphur dioxides and ozone, do infiltrate buildings. Over time, they will corrode your bronzes (Grontoft et al, 2016). Rub on micro-crystalline wax and burnish with a bristle brush or cotton rag as you might your shoes. It will improve the bronze’s lustre and retard surface change.
3: Internal materials like wooden floorboards and furniture emit acidic gases such as acetic or formic acid. These will damage your bronzes particularly if air flow is static and where temperature of a room is likely to fluctuate widely. Consider where you locate your small bronzes and try not to display them in sealed cabinets made from materials containing hard and soft woods or plywood (Gibson, 2010)
4: Avoid handling your bronzes. If possible, lift your bronzes with a clean cloth rather than touch them directly. Sweat from the hands is acidic and will corrode metal easily penetrating a thin barrier layer like wax.
5: If you are storing a small bronze rather than displaying it. Ensure that the packaging materials are suitable. Do not wrap bronzes directly in bubble wrap or plastic. Houses tend to have poor humidity controls and though it might surprise you – bronzes do hold water. When they heat up that water will evaporate and if you’ve trapped it in plastic – you’ll get corrosion overload happening beneath that plastic.
6: If you accidentally spill red wine, tea, coke or even water on your bronze – don’t ignore it! Just because it’s not a textile that stains – don’t assume that the liquid won’t do any harm. If you whip it off quickly then harm is averted, but leave it to dry out and the metal will etch in the perfect shape of the drip, splash or spill. A little warm water on a clean cloth as dry as possible will enable you to remove the liquid and save your bronze surface. Don’t forget to dry your bronze after you’ve washed it though and replace the wax.
7: Admire your bronze often – don’t ignore it. If you keep an eye on your bronzes you will notice if there is any change occurring. Although we all like a beautiful mature patina on a bronze, if the bronze is starting to change within a short period of time then the chances are it is being exposed to something that isn’t doing it a lot of good. Be mindful and you could prevent a bigger conservation problem.
8: Think about where you locate your bronze. If a bronze is in a busy area of the house, its chances of being knocked, and scuffed rise considerably. Bronze looks tough, but often small bronzes have delicate sculptural detail and one bang can see sections break off or snap. Dents are very hard to remove successfully. Drafts also carry outdoor pollutants inside and humidity is likely to peak and trough more which won’t do your bronzes any good.
9: If you want to give your bronze the Rolls Royce treatment then a high-spec display case made with materials that do not emit gases will go a long way. Though undoubtedly an expense, it has been shown that cases with robust seals prevents traffic pollution getting in, provides extra security if you are burgled, prevents household damage like spills and knocks. A low and stable relative humidity under 40% is ideal. It’s also wise to add a little activated carbon into the base of the case in order to absorb any stray pollutants.
10: If you notice a greenish, powdery deposit on your bronze which is easily brushed away, but returns quickly – get it to a conservator ASAP! This is active corrosion and needs quick, skilled treatment to prevent metal loss.
If you would like help or advice on your small bronze, call Antique Bronze Ltd on 0208-340-0931
Terje Grontoft, David Thickett, Paul Lankester, Stephen Hackney, Joyce H. Townsend, Kristin Ramsholt & Monica Garrido. “Assessment of Indoor Air Quality and the Risk of Damage to Cultural Heritage Objects using MEMORI dosimetry” Studies in Conservation 61:sup 1, 70-82. Routledge & IIC 2016 Link Here
Gibson, L.T. (2010) Acetic and formic acids emitted from wood samples and their effect on selected materials in museum environments. Corrosion Science, 52 (1). pp. 172-178. ISSN 0010-938X