ORE is directly issued to your wallet when you claim it. So even if level 10 mining site can hold a maximum of 10 ORE, you can simply use the collect action multiple times till you are ready to buy a CONVERTER.

The luck factor or RNG is not applied to collect action. So you'll get the amount you are collecting. It's only when you try to convert ORE into MUT, RNG comes into play. It acts like a controlling factor for MUT production.