The many nations of Viir use a silver based economy. Copper and gold coins are in circulation, but their value is based on that of silver.
240 silver pieces = 1 pound of silver
1 gold piece = 80 silver pieces
1 pound of gold = ~16.8 pounds of silver
Valuation of treasure distributed in coin will be given in its value in silver, not the actual number of coins. Characters may end up with pouch valued at several thousand silver pieces, but in reality only have a medium pouch of gold.
For Encumbrance purposes: (This will likely only come into play with a large treasure haul, if ever.)
528 silver pieces = 1 kg
111 gold pieces = 1 kg (valued at 8,880 silver)