News from the conservation studio - Sparkling Silver
SPARKLING SILVER - CHRISTMAS IS THE TIME TO WINE, DINE AND SHINE… At P&O Heritage we are lucky enough to have a wonderful Collection of English, Indian and even Egyptian Silver. Our earliest silver dates from the early Victorian period and includes a magnificent dinner service presented to one of P&O’s founders, Arthur Anderson in 1855 and still in the Company’s care today. The job of keeping our silver sparkling falls to our conservator, Anna-Klara Hahn, who we have asked to share some of her trade secrets…
About Silver
Silver (Ag) is a white and soft metal that gets damaged and dirty easily and it reacts with the air.
It scratches and dents easily with rough handling and even the lightest touch can be harmful. The salts and grease in our skin are highly corrosive to metal. Our fingerprints actively corrode the silver and are very difficult to remove. It is therefore best to handle silver with clean cotton or disposable vinyl gloves to stop oils from hands passing onto the metal.
Silver blackens, tarnishes and corrodes in the air by reacting with different substances in our environment, for instance from industrial pollutants, such as fumes from vehicle exhausts.
Tarnish is a corrosive process and appears as a gradual discolouration from yellow or pink, to brown, dark grey then black. This layer consist mainly of black silver sulphide, which is caused by sulphur containing compounds in the air such as hydrogen sulphide. Other common material such as wood containing formaldehydes; protein based materials such as wool, felt, silk, leather and acids from cardboard, paper and plastics also contributes to silver corroding.
Did you know: Silver actually tarnishes faster when it is stored in a damp environment.
How to look after your Silver -
Top Basic Cleaning Tips
Gently does it!
- Over-cleaning of silver with abrasive polishes should be avoided, as every time silver is cleaned a small part of metal is always removed, therefore it is important to minimise this.
- Always dust carefully – silver scratches easily – use a soft cotton cloth or brush! Always ensure both dust and grease are removed before buffing with a silver cloth as they could scratch the surface.
Know your Tarnish!
- Light Tarnish: For silver that is used regularly and just looking a little dull or yellowing and is lightly tarnished:
- Wash silver object with a mild detergent in warm, clean water
- Rinse in clean water and dry with a cotton cloth.
- Wipe with a clean silver impregnated cloth and buff gently to give a preventive coating and sheen to the silver object.
B. Medium Tarnish: For silver that is medium tarnished or is a composite object e.g. made or composed of moisture sensitive materials, such as bone, ivory, bakelite or wood handles and bases:
- For a more controlled application, use cotton swabs dipped in methylated spirit to degrease the silver surface.
- Wipe with a clean silver impregnated cloth and buff gently to give a preventive coating and sheen to the silver object.
C. Heavy Tarnish: For silver that is heavily tarnished, e.g. brown or black:
- Use diluted silver polish in water – apply sparsely with a soft cotton cloth, cotton swabs or soft brush and rub gently.
- Rinse thoroughly – ensure all polish residue has been removed from the crevices in your silver. Use fine soft brushes or damp cotton swabs, if needed.
Wipe with a clean silver impregnated cloth and buff gently to give a preventive coating and sheen to the silver object.
For long term protection a protective coating such as acrylic or nitrocellulose lacquers and microcrystalline waxes can be used to reduce re-tarnishing, but these are difficult to apply evenly and it is therefore highly recommended to consult a conservator for this.
STORAGE GUIDELINES
To prevent re-tarnishing, display and store silver in a stable environment. The recommended guidelines are to keep the levels of humidity below 65% RH.
Try to keep all silver clean and free from dust. Dust collected in the air will absorb moisture in a damp environment and start to corrode the silver.
- Cover silver objects under a sheet of washed cotton or linen cloth, or wrap them in acid-free tissue and place in polythene zipped bags.
- To further reduce re-tarnishing, sulphur absorbing materials such as activated charcoal cloth or silver impregnated cotton bags can be used.
- For silver objects on open display, moisture absorbing material such as silica gel can be used to buffer any humidity changes.
