Gold bullion, for investment purposes, is typically characterized by a minimum purity of 99.5% gold (24 carat, 999 fineness), with the standard "Good Delivery" bar being 400 troy ounces (approximately 12.5 kg). 

The standard gold bar held and traded internationally by central banks and bullion dealers is the Good Delivery bar with a 400 ozt (12.4 kg; 27.4 lb) nominal weight. However, its precise gold content is permitted to vary between 350 ozt (10.9 kg; 24.0 lb) and 430 ozt (13.4 kg; 29.5 lb).

Here's a more detailed breakdown of gold bullion specifications:

Purity and Fineness:

Minimum Purity:

To be considered investment-grade, gold bullion must have a minimum purity of 99.5% (24 carat, 995 fineness). 

Fineness:

Fineness refers to the parts per thousand of pure gold in an alloy, commonly expressed as 999.9 for 99.99% pure gold. 

Caratage:

The carat system, based on 24 parts, is another way to describe gold purity, with 24 carat representing pure gold. 

Standard Gold Bar (Good Delivery Bar):

Weight:

The standard weight for a "Good Delivery" bar, as defined by the London Bullion Market Association (LBMA), is 400 troy ounces (approximately 12.5 kg). 

Weight Range:

The LBMA allows for a slight variation in weight, with the acceptable range being between 350 and 430 troy ounces. 

Appearance:

Good Delivery bars must be free from surface cavities, irregularities, and excessive shrinkage, and they should be convenient to handle and stack. 

Markings:

Mandatory markings include the serial number, assay stamp of an acceptable refiner, fineness, and the year of manufacture, stamped on the larger surface of the bar. 

Other Common Sizes:

100g, 100 oz, 1 kilo, 10 oz, 1 oz:

These are common sizes for gold bars and coins, catering to different investor needs. 

Krugerrands:

These are popular gold bullion coins, available in various sizes, and are 22 carat gold (containing 11/12 24 carat gold and 1/12 copper).


Gold bullion, for investment purposes, is typically characterized by a minimum purity of 99.5% gold (24 carat, 999 fineness), with the standard "Good Delivery" bar being 400 troy ounces (approximately 12.5 kg). 
Here's a more detailed breakdown of gold bullion specifications:
Purity and Fineness:
Minimum Purity:
To be considered investment-grade, gold bullion must have a minimum purity of 99.5% (24 carat, 995 fineness). 
Fineness:
Fineness refers to the parts per thousand of pure gold in an alloy, commonly expressed as 999.9 for 99.99% pure gold. 
Caratage:
The carat system, based on 24 parts, is another way to describe gold purity, with 24 carat representing pure gold. 
Standard Gold Bar (Good Delivery Bar):
Weight:
The standard weight for a "Good Delivery" bar, as defined by the London Bullion Market Association (LBMA), is 400 troy ounces (approximately 12.5 kg). 
Weight Range:
The LBMA allows for a slight variation in weight, with the acceptable range being between 350 and 430 troy ounces. 
Appearance:
Good Delivery bars must be free from surface cavities, irregularities, and excessive shrinkage, and they should be convenient to handle and stack. 
Markings:
Mandatory markings include the serial number, assay stamp of an acceptable refiner, fineness, and the year of manufacture, stamped on the larger surface of the bar. 
Other Common Sizes:
100g, 100 oz, 1 kilo, 10 oz, 1 oz:
These are common sizes for gold bars and coins, catering to different investor needs. 
Krugerrands:
These are popular gold bullion coins, available in various sizes, and are 22 carat gold (containing 11/12 24 carat gold and 1/12 copper).

Gold bullion, for investment purposes, is typically characterized by a minimum purity of 99.5% gold (24 carat, 999 fineness), with the standard "Good Delivery" bar being 400 troy ounces (approximately 12.5 kg). 
Here's a more detailed breakdown of gold bullion specifications:
Purity and Fineness:
Minimum Purity:
To be considered investment-grade, gold bullion must have a minimum purity of 99.5% (24 carat, 995 fineness). 
Fineness:
Fineness refers to the parts per thousand of pure gold in an alloy, commonly expressed as 999.9 for 99.99% pure gold. 
Caratage:
The carat system, based on 24 parts, is another way to describe gold purity, with 24 carat representing pure gold. 
Standard Gold Bar (Good Delivery Bar):
Weight:
The standard weight for a "Good Delivery" bar, as defined by the London Bullion Market Association (LBMA), is 400 troy ounces (approximately 12.5 kg). 
Weight Range:
The LBMA allows for a slight variation in weight, with the acceptable range being between 350 and 430 troy ounces. 
Appearance:
Good Delivery bars must be free from surface cavities, irregularities, and excessive shrinkage, and they should be convenient to handle and stack. 
Markings:
Mandatory markings include the serial number, assay stamp of an acceptable refiner, fineness, and the year of manufacture, stamped on the larger surface of the bar. 
Other Common Sizes:
100g, 100 oz, 1 kilo, 10 oz, 1 oz:
These are common sizes for gold bars and coins, catering to different investor needs. 
Krugerrands:
These are popular gold bullion coins, available in various sizes, and are 22 carat gold (containing 11/12 24 carat gold and 1/12 copper).