A long standing source of interest (and humour) comes from the allusion of Tolkien to female Dwarves having beards, which was borrowed by other writers. Essentially, Tolkien developed a rational explanation for why female Dwarves are never encountered in the story, by elaborating that female Dwarves never travel abroad, and look so much like Dwarf men that visitors to Dwarf cities cannot immediately spot them. In addition to being rare creatures they are perhaps not often featured in many fantasy milieu for this reason.
Tolkien writes his Dwarf-women are "in voice and appearance, and in garb if they must go on a journey, so like to dwarf-men that the eyes and ears of the other peoples cannot tell them apart." This, he writes, leads to the belief that Dwarves grow out of stone[15]. In The Chronicles of Narnia, in fact, C. S. Lewis, who was a friend of Tolkien, describes his Dwarfs as doing just this, and it is possible that Tolkien was ribbing Lewis in making this point. Interestingly, though, Lewis' all-male Dwarfs are capable of mixing with humans to make half-Dwarfs, such as Doctor Cornelius, the tutor of Prince Caspian (In the 2008 adaption of Prince Caspian, female Dwarfs are shown as archers along with the males, though these female Dwarfs are shown to be beardless). In later writings, Tolkien directly states that his female Dwarves have beards "from the beginning of their lives", as do the males[16].
