A tip about storing opals
@Lochness Monster. They should be placed in a small plastic bag with a small damp cottonbail, not wet just damp.
Your opal with become brighter and the colours more intense.
Mr G M recently bought a Victorian opal pendant for me and stored it in the manner described above. We were looking at it last night and my goodness, the intensity of the colours is amazing. The damp cotton wool moisturises the opal because an opal is porous. It enhances the colour and clarity. You will find the cotton wool becomes quite dirty if it is an old piece of jewellery.
P.S. I too love antique jewellery.