What type of geodes are these?

I don't know anything about geodes. Got these ones today from my neighbour, and my son is fascinated. What type of geodes are these?

 

Where do you live? They look a little like Keokuk geodes,but geodes are found in many locations around the world.

 

In Mexico, I was told these particular ones are from Zacatecas

 

I saw that similar are sold on ebay just as quartz geodes, Zacatecas, but would like to know if there is more to add to this classification, like the particular type of surrounding stone, etc. Not that it is very important just would like to learn more

 

I don't think there is any particular designation; just quartz geodes; and if one happened to know where they were collected, one could say "from Arizona" or "from China;" but quartz geodes are all pretty similar. Someone with more experience might be able to narrow down the geographical origin, though.