The price of silver is always unstable. The real stable price is gold, so gold can be used as a store of value. BTC has no such potential at present.
Well from my point of view, I think these both have got same level of stability. Theyre different but from bitcoin. When contrast is made, bitcoin is quite more volatile and unstable than gold and silver. But these later two are quite same. They dont move quite impressively. Their movement is much slower than a rabbit. So whatever suits you, true to go towards it?