All those who have torns are the same mamillaria except on of the last pic who is an astrophytum. I guess the ones with jagged are little bit bigger than the others. I dont know if it happens with all cacti i only have those to see xD
I know glochids and opuntia spines have microscopic barbs and what not.
But i would really want to spines under microscope, like ferocactus and echinocactus, or echnopsis. they have some kind of ribs,
And flowers too.
I dont have feros or some others to watch them with the microscope. I guess i have buy some feros to cactus hobby but they dont arrive yet so maybe in few months i can update pics of feros xD