Any difference in granular ferric oxides?

[MattL22]

Someone on my local Fourm posted a place that's sells 12 lbs of Gfo for $125 or 6 lbs for $68

I'm gonna order but was wondering if there's a difference besides granular size? I'm thinking I might try to break it down a bit in a food processor or something to get the sm grain size like rowaphos??

 

[MattL22]

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