Biogenic opal (BSi) concentrations were analysed as indicator for past primary productivity on gravity core MSM45_19-2 from the northern Labrador Shelf. Gravity core MSM45_19-2 was obtained during R/V Maria S. Merian expedition MSM45 (58°45.68'N, 61°56.25'W, water depth: 202 m) in 2015 (Schneider et al., 2016). Biogenic opal was determined at Dalhousie University following the method of (Mortlock and Froelich , 1989). Briefly, amorphous silica was extracted from ca. 20 mg subsamples using a 2 M Na2 CO3 solution at 85°C for 5 h, followed by the measurement of dissolved silica concentrations by molybdenum blue spectrophotometry.