I am busy building a Triac switch to switch a contactor coil 240 Volts, 9VA holding power, 50 Hz and 507 ohms DC resistance. From the VA I calculated Amps 9/240 =0.0375 Amps.

Z = V/I= 6400 Ohms and Xl calculated 6380 ohms using the standard Z,R,XL formula.Z sq= Rsq +XLsq

Am I correct to say that the snubber cap should ideally have the same reactance as the coil, in this case 6380 Ohms? Roughly ).5 Micro farads for 6380 XC ohms?

Since the coil DC resistance is 507 Ohms, is there any sense in having a any series resistance other than the 507 Ohms DC resistance in the circuit and just a 0.5 micro Farad cap over the coil?

It makes sense to me to put the cap over the coil.

Cobus.