What kind of material should I use for a winter cloak?

My mother wanted to buy a winter cloak last year but when we went back to the store a day after seeing them, they were all sold out. We went searching for it in all the stores I saw them in but likewise they had none.It was kind of like a vampiric cloak with a hood but without the high collar. I guess there's still some goth left in her from 20 years ago, ha. Anyways, she really wanted it and I'd like to make her one but I'm not exactly sure what material to use for the outside.