Thats strange, I remember most people valuing it at 1:3. See no reason why it would be 1:2 as gold mines are rarer, and I believe you get less of a chance of getting a nugget with gold ore then you do with a silver.
I'm saying their sell rate is 1:2, people would be a bit....yeah, to sell gold, but people would buy it with ANYTHING they have if they don't own a gold mine already