As the article above highlights, laterite and sulphide deposits have key differences.
To break it down the key differences in their most basic sense
SulphidesAre the prefered type due to the abilty to liberate and recover the nickel in a simple, ESG friendly, derisked proven method (below).
Aston can easily produce a concentrate and sell to either of the two nearby smelters (Sudbury 300km).
New sulphide depostis are
very rare to find, many current companies are restarting historic mines not new discoveries. For them to be successful it is critical for them to find high grade nickel and lots of it to be economically feasible to mine deep underground to recover the Nickel. In a project that requires deep mining to recover thin veins of sulphides, high grade is critical.
Aston deposit is different.
This deposit is a
NEW discovery, it has never been mined previously, meaning the shallow nickel is still in place.
The metrics of the deposit is very favorable for Aston as they can mine this using open pit methods due to being incredibly large with
40 plus years life of mine and the deposit structure is long and thick.
The sulphides are highly recoverable, not locked up in silicates, no presence of arsenic. The Fe:mgo ratio is suitable for smelting.
93% Liberation of Nickel Demonstrated by Initial Analysis.
Traditionally sulphide deposits are prefered due to the favorable processing methods but majority of sulphides existing today do not provide the long life of mine that laterites can offer.
This is where Aston have best of both, preferrable type AND long life of mine.
LateritesTraditionally laterites are large scale low grade deposits that are mined via open pit methods. Very similar to Aston.
The main difference is that laterites are very difficult to recover and requires huge amounts of energy, chemicals and engineering to acheive recovery. Below is the simplfied flowsheet for HPAL which is one stage of the processing. Clearly there is a higher technical risk associated with Laterites due to the HPAL process.
In conclusion,
Aston have the advantages of laterite ore bodies being large scale and surface mining without the negative of increased technical risk due to HPAL processing. This allows Aston to successfully provide a long supply contract for a western sourced EGS compliant product.
Source:
https://www.researchgate.net/figure/Simplified-traditional-process-flowsheet-for-the-extraction-of-Ni-Cu-and-Co-from-nickel_fig1_360648053https://www.researchgate.net/figure/High-pressure-acid-leaching-HPAL-process-flowsheet-operating-at-Moa-Bay-Adapted-from_fig3_328157943
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