Sebum, skin cells and bacteria producing the same fatty acids found in ripened cheese. Why it happens, how to stop it, and how to tell normal build-up from an infection.
Opal holds water, which is why ultrasonic cleaners and hot taps destroy it. How to tell a solid opal from a doublet, and why submerging the wrong one clouds it in seconds.
Three tests that work — the 925 stamp, a magnet and an ice cube — and three that ruin the piece. Plus why tarnishing is evidence for real silver, not against it.
It's copper reacting with sweat, it washes off, and it does not mean the piece is fake — real sterling does it too. Plus how to tell a green stain from an actual nickel allergy.
A suitcase is a pile of chains shaken for six hours. The drinking straw beats every jewellery roll on the market, and the zip bag everyone recommends is wrong for silver.