For gold, this is one fine troy ounce, and for silver, one troy ounce. In the case of gold, the unit represents pure gold irrespective of the purity of a particular bar, whereas for silver it represents one ounce of material of which a minimum of 999 parts in every 1,000 will be silver.
The traditional unit of weight used for precious metals. The term derives from the French town of Troyes, where this unit was first used in the Middle Ages. One troy ounce is equal to 1.0971428 ounces avoirdupois. In the bullion market, all references to ounces mean troy ounces.
The Loco London Spot Price
This is the basis for virtually all transactions in gold and silver in London. It is a quotation made by dealers based on US dollars per fine ounce for gold and US dollars per ounce for silver. Settlement and delivery for both metals is two good business days in London after the day of the deal.
From this basis price, dealers can offer material of varying fineness, bar size or form - for example, grain - at premiums to cover the costs of producing smaller, exact weight bars, or bars of a fineness above the minimum 995 fine.
Unit for Delivery of Loco London Gold
This is the London Good Delivery gold bar. It must have a minimum fineness of 995.0 and a gold content of between 350 and 430 fine ounces with the bar weight expressed in multiples of 0.025 of an ounce - the smallest weight used in the market. Bars are generally close to 400 ounces or 12.5 kilograms.
Unit for Delivery of Loco London Silver
This is the London Good Delivery silver bar. It must have a minimum fineness of 999 and a recommended weight between 750 and 1,100 ounces, although bars between 500 and 1,250 ounces will be accepted. Bars generally weigh around 1,000 ounces.
Both gold and silver bars must conform to the specifications for Good Delivery set by the LBMA. Further information can be found in the Good Delivery section.
Other Bullion Bars
A variety of smaller exact weight bars is available to wholesale clients in addition to Good Delivery bars. The fine gold content of exact weight bars is determined by their fineness. A client pays only for the fine gold content. Silver kilo bars are purchased and sold as one kilo of 999 fine silver.
Bar Weights and Their Agreed Fine Gold Content in Troy Ounces