Cosmo completed a 1500m RC drilling program last year, and while it was optimistic of success given pXRF data, the assays have confirmed the presence of mineralisation with early parallels to the prolific Teutonic Bore discoveries, such as Jaguar and Bentley.
The Minjina drilling delivered a headline 7m at 3.2% zinc, 0.92% lead and 11.84 grams per tonne silver from 73m, including 2m at 5% zinc, 1.4% lead and 18.83gpt silver.
Lower grade mineralisation was intersected from 28m, and down to about 120m.
The pXRF data that suggested a 49m-wide zone of elevated zinc from 41m.
The hole was designed to follow up historical drilling completed by Gold Road Resources in 2015, some 80m away, that returned 12m at 0.8% zinc, 0.16% lead and 3.3gpt from 48m, including 2m at 2.13% zinc from 58m.
Managing director James Merrillees said the hole was an "outstanding result" for its first Minjina drilling, confirming the mineralisation was thickening, and it may have nicked the distal edge of a larger system.
The mineralisation is unconstrained within a 1km by 750m zone of elevated zinc, and may be the footwall zone of a deeper, potentially more massive, mineralised system.
The program also intersected Mt Venn-style mineralisation in additional holes, such as 3m at 0.37% copper, 0.06% nickel and 0.18% cobalt from 7m, over two additional zones: 12m at 0.44% copper and 0.08% nickel from 12m, including 1m at 1.31% copper from 24m, and 20m, at 20m at 0.21% copper, 0.10% nickel and 0.03% cobalt from 45m.
Minjina is about 1km from the company's flagship Mt Venn deposit, and the presence of Mt Venn-style mineralisation at Minjina potentially almost doubles the strike length of the shallow copper-nickel-cobalt system to 2.4km.
The 0.18% cobalt intersection is the highest-grade intersection for the metal across the Yamarna project, which Cosmo suggests may reflect interaction with the VMS system intersected 70m to the south.
An off-hole electromagnetic target, and remodelling of several "near-miss holes" has already provided Cosmo further walk-up drill targets. It expects to add more with a follow-up ground geophysics program.
A rig has been contracted to test the first new targets next month.
Minjina was only defined last year with two strong EM conductors coincident with widespread copper soils anomalism.
Shares in Cosmo, which spun out of
Great Boulder Resources, were up some 22% in early trade at an intraday peak of 19c.
At the time of writing, the stock was still up 10% at 16.5c, valuing the explorer at $8 million.
Cosmo shares have traded at 12-25c over the past year.