Prevost, who is involved in South African Code for the Reporting of Mineral Resources & Mineral Reserves (Samrec) on the coal side, also indicated that Samrec will soon be rewritten.
This rewrite will be in line with the latest international developments in international codes and will involve more stringent classifications.
Meanwhile, the inventory - which is now close to completion - should give South Africa some idea of where the fuel to power the energy upswing will be coming from.
While already some time in the making, those in industry who contributed to financing it have already been making use of the guidelines in their own reporting.
The first attempt known to work out where South Africa's coal reserves were located was in 1983, when De Jager determined that 30% of all coal reserves lay in the Waterberg in his paper 'Coal Reserves of the RSA 1983 - and Evaluation at the end of 1982'.
Now, with the separate classifications of reserves and resources, much of this has been demoted to resources, and the Waterberg's 'reserves' have dwindled to 3% - from 30%.
In 1983, this area was thought to contain most of South Africa's coal. Second was Witbank at 22% and this area was followed by the highveld at 19%.
In 1987 Bredell undertook another survey under the title 'SA Coal Resources, Explained and Analysed'.
This survey, using methodology based on UN classification codes, did not vary much from De Jager's survey.
As such, said Prevost, clarity as to actual reserves was needed.
In 2004, the minerals bureau, under the auspices of the DME undertook a new survey using the Samrec codes.
The new information painted a rather different picture.
Some 35% of South Africa's coal was now to be found in the highveld, and the coal-rich Waterberg saw much of its reserves pronounced as resources, leaving it with 3%.
Witbank accounts for 33% of coal reserves while 15% is at Ermelo.
Now, some 90% of South Africa's coal reserves are seen to be in the Central Basin area that includes Witbank, Ermelo and the highveld.
This area also accounted for 81% of South Africa's output last year, said Prevost.
Yet not all is lost for the Waterberg.
As its coal has simply been reclassified from mineable reserves to resources, exploration could indicate that there are substantial reserves there, and such a project is already happening.
Worldwide, reporting codes trace its 'birth' back to a UN classification code, which looked at reporting in three dimensions.
Samrec itself was launched in South Africa in March of 2000.
To cover commodities such as diamonds and coal, specific codes were given life, and the one that covers coal is known as SANS 10320.