Annex – London Good Delivery Bar Weighing – Conversions, Rounding and Tolerances

The principles applied to the weighing of LPPM Good Delivery bars are that the weight stamped on a bar, by the producer/refiner is a minimum weight, in the same way the purity stamp of 99.95% is a minimum purity. The producer/refiner should expect to be credited with the stamped weight and any subsequent physical movement of these bars out of the clearing system should also reflect the stamped weight on the relevant bar lists.

The LPPM however accept their can be minor differences in weighing equipment and for practical and clarity purposes have set out the rules below.

Conversions, Rounding and Tolerances
Weight Stamping The weight of the bars can be stamped either in metric (kilogram or gram) or troy ounces as per the current good delivery rules. These should however have the following number of decimal places:-
  • Troy Ounces : 3 places
  • Kilogram : 4 places
  • Gram : 1 place
N.B. When a bar is weighed at the point of production to decimal places in addition to those stated above, these decimal places should be ignored and NO rounding, up or down should take place.
Rounding Weight lists will be in troy ounces or converted from kg with the following conversion from metric formula:
  • A standard conversion rate from kilograms to troy ounces of 32.1507465 to produce a 5 decimal figure.
  • Rounding: if upon conversion to troy ounces the last two digits were 75 or greater the third decimal place should be rounded up and if the last 2 digits were 74 or less the third decimal place in the troy ounce weight should remain unchanged.
For Bars dated 2014 or before
Weight Tolerance When the troy ounces is established, either by conversion or stamped on the bar, subsequent weighing tolerances shall be:
  • Minus: 0.006 troy ounces
  • Plus: no upward limit - the management of this upward limit is to be at the vault manager’s discretion.
For Bars dated 2015 and onwards
Weight Tolerance When the troy ounces is established, either by conversion or stamped on the bar, subsequent weighing tolerances shall be:
  • Minus: 0.003 troy ounces
  • Plus: no upward limit - the management of this upward limit is to be at the vault manager’s discretion.

 

127.1062