Hard rock lithium mines can have much higher greenhouse gas emmissions compared to brines, said Mark Fellows, co-founder of and director at Skarn Associates.On Friday Fellows recorded Kitco Roundtable podcast with correspondent Paul Harris and mininga adiences manager Michael McCrae. Skarn is a UK-based consultancy that quantifies and benchmarks asset-level greenhouse gas emissions, energy intensity and water use across the mining sector.Transportation, conversion and refining of hardrock lithium all lead to much higher greehouse gas output compared to brines. Fellows said his company will be studying water usage at brines.