Mammoth Minerals (ASX:M79) said the first-ever 3D underground survey of its US-based Excelsior gold-silver project's Blue Dick Mine has revealed 345 meters of historical development across two levels and multiple areas of stoping, according to a Tuesday Australian bourse filing.

The company said that systematic mapping, rock chip sampling, and channel sampling of exposed mineralization within the underground workings are now underway to help guide further exploration by increasing the company's understanding of the geometry of the mineralization.

Initial interpretation indicates that the Blue Dick Mine trend extends for 2.9 kilometers of strike across multiple historic workings, the filing added.

The company added that the diamond drill rig is being mobilized to the site this week ahead of the initial drilling program across the Buster trend, which extends for a strike length of five kilometers.