I have measureed M(emu/g) versus H(Oe) curve. Now i want to find the initial permeabilty from it. Althought i know we can calculate susceptability from MH curve by calculating dM/dH, then by adding 1 we can get initial permeability. We need to draw a tangent to a point on initial magnetization curve. But for tanget which point do we need to consider on initial magnetization curve. Also how about unit conversions in CGS? and how can we claculate initial susceptability from MH curve