The intercept graded 9.07g/t gold and 76g/t silver, and included 27.77m at 13.06g/t gold and 84g/t silver, or 14.18g/t AuEq.
The company said the phase one drilling programme was designed to infill and upgrade areas of the 21A zone which it said had previously been disregarded.
"Despite the substantial precious metal grades and base metal credits of the 21A Zone, in the opinion of the company, the low commodity prices combined with smelter penalties and necessary cut-off grade deemed the 21A Zone historically uneconomic," it said.
"As well, antimony was treated as a penalty element and now has the potential to offer significant by-product credits."
Skeena has the option to acquire 100% of the former high-grade mine from Barrick Gold under a deal struck less than a year ago.
It announced a maiden resource for Eskay Creek last month, including an indicated openpit resource comprising 207,000oz AuEq and an underground indicated component of 814,000oz AuEq.
Skeena also owns Barrick's former Snip mine, where London-listed Hochschild Mining can earn up to 60% after making a C$6.8 million (US$5.2 million) investment at an 80% premium in the junior in October.
Shares in the company closed down about 6.5% yesterday to C36c.
That price is towards the lower end of the 52-week range of 29c-80c and capitalises it at $35.2 million.