The opaxe Index

Opaxe calculates two indexes – the Original opaxe Index and the Current opaxe Index – relating to drilling results.

The Original opaxe Index is calculated using commodity prices from the date of the original company announcement i.e. drilling results released on 3 January 2021 will be converted into an opaxe Index using commodity prices from 3 Jan 21. 

The Current opaxe Index is calculated using the latest commodity prices, i.e. drilling results from 30 June 2020 will be converted into an opaxe Index using the latest commodity prices from the date of the search that involves the drilling results. The two opaxe Indexes are shown in search results.

The commodities that are converted for comparison purposes are: Iridium, Platinum, Palladium, Rhodium, Ruthenium, Silver, Aluminium, Copper, Iron, Lead, Nickel, Tin, Tungsten, Zinc, Cobalt, Lithium, Molybdenum, Uranium, and Vanadium. 

The formula used to convert drill intercept grades to gold equivalence is as follows:

Where AuEq (g/t) is the gold-equivalent grade, z is the number of listed components (e.g. Au, Ag, Pb, Cu, Zn, Li2O, Sn, Co etc), ρ𝑛 and 𝑉𝑛 are the mass concentration and market value of the 𝑛 𝑡ℎ component in the list, respectively, and 𝑉𝐴𝑢 is the market value of gold.

The AuEq has been calculated using current commodity prices that may be found at the following sites:


 Gold has been chosen as the metal equivalent for all conversions as it is the most widely used and best-understood benchmark to determine or appreciate the grade tenor of a drilling intercept. Opaxe has not investigated and is not aware of the detail of metallurgical recoveries used in the conversions for each drilling intercept mentioned in the opaxe website. It is uncertain that all the elements included in the metal equivalents calculations have a reasonable potential to be recovered and sold. For many projects at the Exploration Results stage, metallurgical recovery information may not be available or able to be estimated with reasonable confidence.

The opaxe Indexes are a convenient way to compare drilling results across commodities and time. They should not be used in any technical or financial analysis or valuations etc of companies or projects or for investment decisions.