Yes, that is awkward. In alchemic lore, there are projections and steps in the process that would let you turn base metals into silver, but this is extremely obscure stuff and so Griphook jumping from ‘ton of silver’ to ‘possession of a Philosopher’s Stone’ looks simply like an error on the author’s part since 99.9% of everyone reading it only knows of the Stone turning base metals into gold and not silver.
The expression is “the medicine of metals”, I think — the use of the Stone of the Wise to heal metals of the infirmity which causes them to be less noble than gold.
Yes, that is awkward. In alchemic lore, there are projections and steps in the process that would let you turn base metals into silver, but this is extremely obscure stuff and so Griphook jumping from ‘ton of silver’ to ‘possession of a Philosopher’s Stone’ looks simply like an error on the author’s part since 99.9% of everyone reading it only knows of the Stone turning base metals into gold and not silver.
The expression is “the medicine of metals”, I think — the use of the Stone of the Wise to heal metals of the infirmity which causes them to be less noble than gold.