The geological setting of the Hamn Nickel Deposit, Senja, Troms

The Hamn gabbro on Senja is an arcuate body extending from Hamn in the N to Gryllefjordbotn in the S, a distance of just under 10 km. Its average width is ca. 2 km. Its age is 1800±3 Ma, based on U-Pb dating of zircon. The Ni mineralization at the shore at Hamn was mined from 1872-1886, yielding 105,000 t of ore: c. 1000t of nickel and cobalt and 500 t of copper were produced from ore with an average grade of 0.9%Ni. The main ore lens at Hamn is c. 80 m long and 15 m wide at the surface, plunging and wedging out downwards towards the ESE. This report is based on data provided by Store Norske Gull - a report by Makkonen (2007) and the results from six hoies drilled in 2008 -and on data from NGU's databases, as well as a limited amount of fieldwork.