A method, apparatus and computer-readable medium for estimating a mass of silicates in a fluid flowing in a member is disclosed. A magnetic field is induced in the fluid to align nuclei of the fluid along a direction of the magnetic field. A radio frequency signal is transmitted into the fluid from a transmitter to excite silicon nuclei present in the fluid. A signal is received from the silicon nuclei responsive to the transmitted radio frequency signal at a receiver. A processor estimates the mass of silicates in the fluid directly from the received signal.