Many plant foods provide excellent calcium: collard greens (268mg per cup), fortified plant milk (300mg per cup), tofu (253mg per half cup), and tahini (426mg per 100g). Absorption rates vary - calcium from low-oxalate greens like kale is absorbed better than from high-oxalate spinach.

Blackstrap molasses has 400mg calcium per 2 tablespoons. I add it to oatmeal.

The Adventist Health Study found that vegetarians have similar bone density to meat-eaters when calcium intake is adequate.