Once you budding McDucks begin stacking, it probably doesn't hurt to be aware that silver can be delicate and should not be stored with gold.
Tarnishing and Corrosion:
Silver tarnishes easily, and when stored with gold, it can transfer this tarnish to the gold, causing discoloration.
Galvanic Corrosion:
When two different metals are in contact, they can create a galvanic cell that accelerates corrosion, potentially damaging both metals.
Alloys and Purity:
Different types of gold (like 10k, 14k, 18k, etc.. up to but not including pure 24k) have different alloy compositions, and these alloys can react differently with silver, leading to potential issues.
Physical Damage:
Even without chemical reactions, storing items together can lead to scratching or denting, especially if they are different shapes or sizes.
These are issues for bullion, numismatic coins, or jewelry items.