We have constructed a Faraday magnetometer to measure the nuclear magnetiza
tion of monolayer He-3 films at temperatures down to 100 mu K and in magnet
ic fields higher than 10 T. An estimated resolution of the magnetization me
asurement is higher than 1 x 10(-10) JT(-1). This performance is sufficient
to resolve 0.1% of the total magnetization of monolayer He-3 adsorbed on a
n exfoliated graphite with surface area of 1.5 m(2). (C) 2000 Published by
Elsevier Science B.V. All rights reserved.