Are bacteria capable of precipitating magnesite?

Abstract

 Laboratory experiments were conducted to investigate the possible (bio-) chemical pathways involved in the low-temperature nucleation of magnesite, MgCO₃. Two compounds known for their power to prevent hydrolysis (amorphous silica and magnesium trisilicate) were tested in contact with a slowly desiccating solution of magnesium bicarbonate. Amorphous silica gave rise to precipitates of nesquehonite instead of the more usual magnesium hydroxide carbonate, thereby illustrating its influence on hydrolysis. Magnesium tri-silicate led to Xray amorphous precipitates. The presence of reducing compounds, in particular the strongly reducing hydrogen gas, does not lead to the low-temperature nucleation of magnesite.