G50 Corp Lifts Golconda Gallium Grades Through Low-Cost Processing

G50 Corp (ASX: G50) has reported proof-of-concept metallurgical results showing that conventional processing can upgrade gallium and recover precious metals from oxidised surface material at its wholly owned Golconda Project in Arizona.

Screening and desliming upgraded gallium grades by as much as double while recovering 63% to 87% of the contained metal into between 40% and 60% of the original sample mass.

The results provide processing options for a combined gallium, gold and silver concentrate or separate gallium and precious metal products.

Performance broadly matched tests on unoxidised material reported in April 2026, supporting further evaluation of a common processing strategy across both material types.

Fine Fraction Hosts Gallium

SGS Lakefield completed the latest work on four 10-to-20 kilogram subsamples selected from a 2,200kg outcrop and trench sampling campaign at Golconda’s Little Jimmy area.

Gallium was concentrated strongly in material smaller than 20 microns, while gold and silver were distributed more broadly across the tested size range.

30% to 70% of the gold and 60% of the silver reported to the gallium-rich fine fraction, creating potential for precious metals to contribute as co-products within an initial concentrate.

Earlier mineralogical work found that about 88% of Golconda’s gallium was hosted in muscovite, establishing the mica mineral as the principal target for concentration and extraction.

Flotation Adds Product Flexibility

Sulphide flotation of deslimed material increased gold grades by about 10 times and silver grades by about five times, with respective recoveries of 70% to 90% and 30% to 50%.

The single-stage open-cycle test demonstrated selectivity for gold and silver-bearing minerals, although most silver in the tested samples had already reported to the fine fraction before flotation.

Separate mica flotation upgraded gallium by two to five times from the feed, recovering 40% to 50% of the metal into about 10% to 20% of the flotation feed mass.

G50 identified scope to use scavenger flotation to lift overall gallium recovery and cleaner flotation to improve concentrate grades as it develops the preliminary processing flowsheet.

Further Work to Test Viability

Golconda hosts gold, silver, zinc, and gallium mineralisation defined over an area approximately 1,300 metres long, 400m wide, and extending to about 400m depth through nine diamond holes and 45 reverse circulation holes.

The current program remains preliminary and used a limited number of surface samples, meaning it does not establish a mineral resource, ore reserve, or the technical and commercial viability of a development.

Mineralogy, liberation, and geochemistry studies on the oxide material remain ongoing, including work comparing impurity-to-gallium ratios with gallium products sourced from aluminium and zinc processing.

Further metallurgical testing will seek broader deposit representation, assess variability, and optimise recovery.

Additional drilling and sampling may also follow from current project studies.