How many grams weight for mm cartridge?

I don’t know guys where are you looking for Grace specs, but go on vinyl engine and check scan of the original grace manual for all models (except Ruby). There is a chart in comparison on page 2 for all of them with tracking force range from 0,5 to 2g for those top f9 models.

@mofimadness 

I have setup hundreds and hundreds and hundreds of turntables and have never seen a cart that tracks at .5 grams.

You may never seen Grace F9 cartridges (F-9F, F-9L, F-9U, F-9D) tracking force range is 0.5 - 2g. I agree that 0.5 is too low, i would say 1g minimum. 

As i can see in the japanese brochure linked by Marin, the most advanced stylus profile in Grace F-8 series and later in Grace F-9 series is F-8F and F-9F stylus profile (Navy Color). Always the most expensive and hard to find nowadays. I wonder why nobody tried and reported about it in "MM thread".

I have great result using Grace cartridges on Luxman TA-1 tonearm made by Misco Seiki for Luxman. The build quality of this arm is superb and much better that Black Widow tonearm.

P.S. Raul, i have not tried 0,5g tracking force with my Grace carts, i think it's too low. I have never use less than 1g. The lowest tracking force i have ever used was between 1g - 1,25g with my Technics EPC 100Cmk3 and 205Cmk4 cartridges.