Chalcedony vs. agate vs. jasper

If this video doesn’t get moved to shorts I’m gonna be sad

[VersaiOnline]

This video would have been super helpful to me a year or two ago!

I'm no expert but I personally feel like jasper doesn't belong under chalcedony, and possibly neither does agate. Definitely all are microcrystalline. Well actually, isn't there another term "cryptocrystalline" that I think is even finer than micro (crystals can't be seen even with a microscope).

I feel like chalcedony is the most specific in that its main definition is translucency. I guess jasper is just opaque chalcedony. Maybe more useful to visualize it as a spectrum, with chalcedony and jasper on opposite ends of the microcrystalline transparency scale. Agate - between the bands can be filled with macro quartz or chalcedony; the band itself could arguably be considered jasper. "Agate" could be alternatively defined as repeated layers of distinct silica formations (chalcedony, jasper, quartz, repeat)

Then there's some "agates" that don't have bands - like plume and moss agates that have filaments suspended in chalcedony. Some banded agate varieties could be considered opaque too, like Dryhead.

Chert and flint seem like subcategories of jasper. All opaque but forming in different ways maybe? Flint forms in chalk beds, something Europe has a lot of but we have almost none of in USA. We have a lot of chert though, associated with limestone beds. Both were sea floor silica oozes that coagulated into nodules. Idk much about jasper, my understanding is massive amounts of it can form when silica infuses into other rock.

And there's different levels to jasper too - the 'porcelain' ones with orbs I believe formed in a unique way to other jaspers.
Banded cherts that can be more patterned than some agates, just opaque.
Silicated rocks, like locally we have a silicated limestone that behaves more like jasper. Or fossils that are 'agatized'; frequently wood.

Sorry, long comment but I like to consider the complexities now