Flakevatn, a high mountain glacial lake situated in central Norway, has been investigated for annual heat budgets, minerogenic and biogenic silica content of water and sediment. Minerogenic silica content was related to potential buffering capacity of glacial ooze during expected glacial ooze event. More accurate estimate of annual heat budget has been deduced from ice cover observations and water column temperatures in the years 2005 and 2004. StrÃ¸m 1965 estimate of Flakevatnâ€™s annual heat budget was recalculated using a different ice cover composition and 6 water column strata to a more reasonable value of 19526 cal cm-2. This lake belongs in a cold monomictic lake category and is estimated to have annual heat budget of 15673 cal cm-2 in the year 2004 and 13074 cal cm-2 in the year 2005.During year 2005, the melt-water did not supply large amounts of glacial ooze and thus did not visibly produce late-summer glacial ooze event in Flakevatn. Turbidity during 2005 was very low but it was observed increasing in mid September due to glacial ooze buildup in the epilimnion. Conductivity and pH of water samples at the epilimnion depths did not significantly change with filtration, but alkalinity did. The dissolved silica measured in inflows to Flakevatn and in reference streams Midtdal and BlÃ¥is has been found to be in a similar value range. This investigation suggests phyllite, a metamorphic mineral common to both locations, as a primary source of dissolved silica.Conductivity and pH were not found to be related to increases in minerogenic silica. Statistical test showed presence of a relationship between an increase in alkalinity and rise in minerogenic silica. This relationship does not have sizeable support due to low number of samples although it cannot be ruled out. Biogenic silica in Flakevatn sediment was the lowest of the three ultraoligotrophic lakes (Klaretjern and Lutvann) examined, suggesting that the silica character of this lake is primarily minerogenic.