Where do these minerals come from ?

[Hari (OP)]

Hello,

New campaign started yesterday.  Version 1. 12, pre-TN, slow game. 
I used SM to create a system and a race. 

My homeworld is generating lots of corundium, as you can see in attachment.  The recent SP change is from a 5-day increment.

I cannot figure where they come from.  No mass driver produced yet, only few mineral orbiter ships on a comet.
I was producing Orbital Mining Modules, I tried to pause/cancel production with no luck. 

Could it be a bug ? Or do you have any idea where they come from ?

[Hari (OP)]

Update : I was producing miner ships using components "Orbital Mining Module" I produced at my colony. 

I stopped the shipyard tasks, and now Corundium income is fine.