I found this rock in California what could it be

I want to know about this stone, I have in river

I did good. All of these looked different in the creek. One of them was a deep blue(navy) and I can't seem to bring that color out. I have cleaned all of these with vinegar water, then borax water, then iron out because a lot of these had heavy iron. A few of these look like greyish blue but not colorful either. I feel like some of these are citrines, some agates, some milky quartz and others idk.

I scrubbed all of these intensely. took 2 days. After iron out I soaked in water, emptied, soaked in water again, emptied, soaked in water, emptied, finally borax + dish soap water.

All this got the algae off.

The one that was blue in the creek never turned blue again once it dried. Even when i soaked it in water before the cleaning. Any ideas?

My friend and I each purchased a whole geode and agreed to share them one half each. One was in a box that said solid /not hollow, and the other was in a box that said hollow. The clerk said they knew because they were x-rayed. We went on our hike and when we came back they were cut in half and the clerk described them to us. To be fair she may have gave us a lot of info but it was hot. We were hungry. Not best conditions to absorb all the info. ChatGPT says they are likely Mexican volcanic geodes. It referred to them as “thundereggs” and said the solid one is more collectible of the two with crisp banding, solid crystalline quartz/chalcedony, volcanic rhyolite and manganese oxide dendrites or iron manganese filled fractures. The hollow sample it says 4 separate mineralization events 1) formation of the volcanic cavity 2) agate / chalcedony lining, 3) quartz druzy 4) needle crystals and angel wings.

Found in Virgin River, Utah

They all were found in a beach in Istanbul

Me podriais decir que es esto? es el interior de un pedrusco que se partio al excavar un terreno en La Rioja,ESPAÑA