I keep seeing theories that like… Jasper is a fusion. And I’m sorry but. That’s not horrifying enough for me. Anyways, the basic facts people have are that? 

• Jasper has irises, like many fusion gems.
  
• Jasper as a rock is an aggregate, or made from multiple gems.
  

Along with this is the theory is hte prevalent theory that Jasper is one of the successful gems made from the Kindergarten on Earth. 

The kindergarten is… regarded as vaguely horrifying by the crystal gems, so it’s obviously. Unnatural in some way. In a way that normal gem creation isn’t. Think of 

So, to summarize the basic assumptions for my theory:

• Jasper is also a kindergarten gem.
  

• Jasper is an aggregate (created from multiple things).
  

• Kindergarten gems are created in a way seen as ‘unnatural’. 
  

Now, one more assumption, something that is shown time and time again throughout the series and implied by the presence of war.

• During and after the war, there were several corrupted gems. Several gems on both sides were destroyed during the war.
  

Now think back again to Jasper’s status as an ‘aggregate gem’.

The kindergarten essentially recycles the bodies of dead or damaged gems. Running out of gems in the war effort, they used the remains of other gems to create new soldiers.

Amethyst is described as ‘overcooked’, likely to the point that it was no longer obvious she was an aggregate.