Old Jelly Cupboard - What Type of Wood??

I have an old Jelly Cupboard, but have no idea what kind of wood it is made of. The back and shelves are very old soft individual wood boards, and the front of the shelves have a crooked wood piece attached so that it forms a lip, to keep items from falling out? The doors and sides, however, are a very very hard wood, absolutely no 'give' to them and very hard to screw into (I replaced the hinges) I have no idea what these are, and would like to know what they are made from, as I plan on selling this cupboard. Also, why would the cupboard be made of two different woods? The cupboard was found in my parents basement, and has been there since at least 1930. I will post picture that shows both the old wood and the 'hard' wood. (The magnets were added later as well) Any help will be appreciated!