I've encountered an issue when it comes to the random ore that is from the mode known as Randomium, the issue I've encountered is the chance to get random multiblock structure blocks from it. These items are harmless if you get them and keep them in your inventory but as soon as you try placing them down in your world. They will proceed to crash your game over and over as the game doesn't know what to do.

This issue was caused because I tried placing a block from Advanced rocketry involving the obitallaserdrill. This block was provided to me when I mined one of the many Random ore blocks you can find in the world. Once I placed it down, the game crashed instantly and was only fixed once I removed the mod. After loading the world back up and re-installing the mod. I was able to fix the issue.

Crash log can be provided if required.