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Good delivery bars

The process of making Good Delivery Bars begins with a process called gold refining or silver refining.
The metal which goes to the refining plant comes from gold mining and silver mining and they are in the form of dorè ingots. Otherwise the raw material is in the form of gold scraps coming from jewellery, goldsmith, silversmith or photographic and electonical components production.
The raw material is refined in 2 different ways: either with the Aqua Regia method or with the Electrolytic Refining.
The assay process is the second step and it’s done to establish the grade of the recovered metal, then the fine metals - gold powder or silver crystals - is melted straight into 400 oz Gold or 1000 oz Silver Good Delivery Bars by mean of a traditional melting pouring and casting process or by mean of a "Flameless Tunnel®" technology, or it could be made into a gold grains or silver grains to be stocked waiting for orders. Once the Good Delivery Bars are made, the logo is printed onto them and, after a weight check the serial number is also printed.

The Good Delivery specification is a set of rules issued by the London Bullion Market Association (LBMA) describing the physical characteristics of gold and silver bars used in settlement in the wholesale London bullion market.
Good Delivery bars are notable for their large size and high purity. They are the type normally used in the major international markets (Hong Kong, London, New York, Sydney, Tokyo, and Zurich) and in the gold reserves of governments, central banks, and the IMF.

Gold bars
• Fineness: minimum of 995.0 parts per thousand fine gold
• Marks: serial number, refiner's hallmark, fineness, year of manufacture
• Gold content: 350 oz t - 430 oz t
• Recommended dimensions
• Length (top): 210 – 290 mm
• Width (top): 55 – 85 mm
• Height: 25 – 45 mm
• Typical denomination: 400 oz gold bars

Silver bars
• Fineness: minimum of 999.0 parts per thousand silver
• Marks: serial number, refiner's hallmark, fineness, year of manufacture, weight (optional)
• Silver content: 750 oz t - 1100 oz t (900 oz t - 1050 oz t recommended)
• Recommended dimensions
• Length (top): 250 – 350 mm
• Width (top): 110 – 150 mm
• Height: 60 – 100 mm
• Typical denomination: 1000 oz silver bars

  • Production process

  • Refining Aquaregia plant

  • Refining Electrolytical plant

  • Assay laboratory

  • Gold & Silver Casting Grains Machines Stopper Technology

  • Gold & Silver Casting Grains Machines Pouring Technology

  • Centrifugal dryer

  • Grain weighting for different formats

  • Flameless Tunnel® (patented technology) G.D. Bars Production Furnace

  • Traditional Pouring Technolgy

  • Logo stamping press

  • Ingots weighting

  • Numerator