Interesting stuff there. Looks to me like you have a mixed event. Had things been a bit cooler it would have been chalcedony but it was not quite cool enough so you had micro-quartz, I've heard it called sugar quartz, crystals form up in layering events with small vugs of druzzy quartz crystals. The grainy appearance are those small compacted crystals. Had it been chalcedony it would probably been much closer to agate in the layered areas. Quartz is a funny thing and seems to be infinite in its variations. Nice stuff.
My opinion.
I noticed this was your very first post Rolltide10p - so, Welcome Aboard! You didn't list your state (or country) in your profile. So, you might consider jumping over to Sub-Forums: Select Your Area.... and selecting location information (i.e., clubs, hunts, finds, legends, maps, etc.) directly related to your state (or country).