Sealing is always the last step in the restoration chain – never the first. A find that has not been completely cleaned, neutralised and thoroughly dried before sealing can continue to corrode under the wax. In this case, sealing traps aggressive substances instead of protecting the metal.

• Find completely cleaned – the coin design and surface are cleanly exposed
• All chemical residues thoroughly rinsed out with distilled water
• Find neutralised – after using acid: pH-neutral soaking or a neutralising solution
• Find completely dried for at least 24–48 hours (room temperature or oven at 50 °C)
• No active bronze disease visible (light green, powdery efflorescence) → special case: section 5
• Objects with enamel inlays, glass stones or brittle patina: cold sealing only – no hot wax!

In the ground, bronze forms a protective patina of copper carbonate and copper oxide – this dark green to brown-black layer is historically valuable and should definitely be preserved. Sealing protects it from further oxidation and environmental influences.

• Final drying of the find Dry the cleaned and neutralised find completely. For thicker objects, briefly pre-warming with a hairdryer on the warm setting helps – the heat opens the pores and improves wax absorption. The surface must be absolutely dry and dust-free.
• Take up a little wax Take up a small dab of Renaissance Wax (about the size of a pea) with a soft, lint-free cotton or microfibre cloth. Renaissance goes a long way – less is more. Do not use a brush, as it applies the layer too thickly.
• Apply thinly and evenly Spread the wax evenly over the entire surface with light, circular movements – including reliefs, recesses and edges. At first the wax remains slightly matt and visibly whitish.
• Let it set Let the wax set for 5–10 minutes at room temperature until it becomes slightly cloudy. For larger objects, wait up to 15 minutes.
• Buff Carefully buff the wax layer with a clean, soft cloth until the surface has an even satin sheen. Work white residues out of recesses with a fine brush or wooden stick.
• Second layer (optional) For particularly porous finds or objects that are handled regularly, a second thin layer is recommended once the first has dried completely (at least 30 minutes). Several thinner layers protect better than a single thick one.

• Melt the wax Heat Cosmoloid H 80 or a professional microcrystalline wax in a water bath to approx. 80–90 °C. Use a thermometer – above 100 °C the wax can decompose. Never heat directly over a flame.
• Pre-warm the object Pre-warm the find with a hairdryer to approx. 60–70 °C. A cold object in hot wax can be damaged by the thermal shock and by residual moisture bubbling up.
• Dip briefly Dip the object into the liquid wax for 3–5 seconds using tweezers or a wire, take it out and let it drip. The wax penetrates the pores and seals from the inside.
• Remove excess and buff Wipe off excess wax immediately with a brush or soft cloth while it is still warm and malleable. Once it has cooled completely, buff with a soft cloth. If necessary, warm briefly with the hairdryer and buff again.

In the ground, silver forms a patina of silver sulphide (greyish to black) or silver chloride (white to grey). This patina has historical value and should be preserved in most cases. Sealing prevents further tarnishing and protects against sulphur compounds in the air.

• Final rinse and drying After cleaning, rinse the find thoroughly in distilled water. Dry for at least 24 hours at room temperature or help it along briefly with a hairdryer (warm air). Complete drying is particularly important with silver – residual moisture under the wax encourages further sulphide formation.
• Optional: Paraloid B-72 as a base layer For very porous or unstable silver finds, experienced restorers recommend first applying a few drops of a 5% Paraloid B-72 solution (available commercially as "The Conservator Fluid"). This conservation fluid stabilises the surface – let it dry completely (15–30 min.), only then apply wax.
• Apply Renaissance Wax very thinly Take a very small amount of wax on a soft cotton cloth and spread it very thinly over the silver surface. On silver, Renaissance is almost invisible – the silvery sheen is fully preserved, and the patina is not covered but subtly enhanced.
• Let it work and buff Let it set for 5–10 minutes, then buff with a clean cloth. Renaissance leaves no cloudiness or discolouration on silver – it changes neither the appearance nor the chemistry of the find.
• Storage in chemically neutral containers Silver is sensitive to sulphur compounds from rubber bands, soft PVC, leather and wool. Only use PVC-free coin capsules or acid-free archival paper – no cellophane bags or cheap plastic bags.

The best sealing is of little use if storage is wrong. Moisture, light, chemical off-gassing from plastics and temperature fluctuations are the greatest enemies of conserved finds.

• Relative humidity: 40–50 % (keep it stable – fluctuations do more harm than a constantly slightly higher value)
• Temperature: 15–20 °C, as constant as possible
• PVC-free, acid-free coin capsules or archive boxes made of polypropylene or polyethylene
• Silica gel sachets in the storage box to regulate humidity
• No direct sunlight and no strong artificial light (UV can yellow wax in the long term)
• No rubber bands, woollen cloth, leather or newspaper near silver finds – these give off sulphur compounds
• No Soft PVC coin pockets for bronze finds – off-gassing promotes bronze disease

• Renaissance Wax (25 ml or 65 ml tin) – all-purpose product for bronze and silver, museum standard
• Microcrystalline restoration wax (e.g. SERVARE, Dark Age Cream Wax) – alternative or supplement for sensitive objects
• Cosmoloid H 80 / hard paraffin – for hot wax application on robust objects without inlays
• Paraloid B-72 (5 %) – conservation fluid as a first layer on unstable or very porous surfaces

• Soft cotton cloths (low-lint) or microfibre cloths
• Household hairdryer for warm-air pre-warming
• Small pot or heat mat for hot wax, plus a thermometer
• Tweezers for hot wax application
• Soft brush for finishing in recesses and grooves
• Wooden sticks or toothpicks for recesses when buffing
• Disposable gloves (nitrile)
• Magnifying glass for quality control

• Benzotriazole (BTA) 3–5 % in isopropanol – the most effective product against active bronze disease
• Distilled water (pharmacy or DIY store) for desalination
• pH test strips to check complete neutralisation
• Safety note: Only use BTA solution with nitrile gloves and in well-ventilated rooms