What would be the best type of fabric to use?

My husband bought me a weighted blanket and I want to make a duvet cover for it. We have pets that sleep in our bed, and since the blanket is so heavy, I don't know if my washer will be able to handle it, especially with how frequently I wash our bedding. I'm not sure what the best fabric would be to use though. I need something sturdy, easy to wash/dry, but also comfortable.