Until you get obsessive, a normal pot is fine for beans. Once you start down that slippery slope, you'll want several different pots for different beans and different cuisines. I refuse to tell you how many pots, metal or clay, I own. You would lose respect for me and question my sanity. But I will introduce you to my favorite pot.
The first reason I love the pot so much is that it was a gift from my Mexican business partners Yunuen and Gabriel. They got it from Lourdes in the Mixteca region of Puebla, near Oaxaca. It's perfect for one pound of beans, although normally I cook half a pound at a time. The round rump encourages the circulation of moisture and the neck is wide enough to allow some evaporation for a rich, delicious pot liquor but not so wide that you constantly have to add water while cooking. The lid doubles as a spoon holder and a bean bowl. You only need it bring the liquid up to a good rapid boil and then you cook without it on a low heat. It's almost magical.
This is Lourdes' mother, prepping the clay for Lourdes to do her thing.The other amazing aspect of this pot is that it's unglazed. After the firing, the mother burnishes the entire pot with stones that have been handed down for generations, creating a glossy finish. I asked Paula Wolfert about this and she thinks it might help with the strength. The best benefit is that there is no lead danger since there is no glaze.
I've said this before but I get such a kick out of thinking that a pot starts here and ends up on my stovetop in Napa. last fall, we started importing the pots and selling them at our store here in Napa. Apparently Lourdes felt this was a terrible waste of time because she just couldn't believe that the North Americans would really use them. She was sure we ate out of cans, if we ate beans at all. When we told we sold out within a month she about fainted. I just love breaking stereotypes on both sides of the border.
We have the pots in our store here in Napa but if you're out of the area, you can also get them at online at Bram cookware, along with dozens of other bean pots and clay-cookware.