In light of Amazon's recent depiction of a non-bearded dwarf woman, and some of the recent controversy around this, the question is what exactly did Tolkien say about bearded dwarf women?
Popular perception, no doubt heightened by the Peter Jackson films, have his lady dwarves as bearded, but did Tolkien actually ever say this?
In c.1951, Tolkien wrote a revision to a chapter of The Silmarillion then titled "Of the Naugrim and the Edain", in which he explicitly stated that:
The Naugrim were ever, as they still remain, short and squat in stature; they were deep-breasted, strong in the arm, and stout in the leg, and their beards were long. Indeed this strangeness they have that no Man nor Elf has ever seen a beardless Dwarf- unless he were shaven in mockery, and would then be more like to die of shame than of many other hurts that to us would seem more deadly. For the Naugrim have beards from the beginning of their lives, male and female alike; nor indeed can their womenkind be discerned by those of other race, be it in feature or in gait or in voice, nor in any wise save this: that they go not to war, and seldom save at direst need issue from their deep bowers and halls. It is said, also, that their womenkind are few, and that save their kings and chieftains few Dwarves ever wed; wherefore their race multiplied slowly, and now is dwindling.
"Of the Naugrim and the Edain" §5, first published in 1994 in The War of the Jewels
Shortly after this, when finishing up work for the appendices of The Lord of the Rings, Tolkien added a similar passage about Dwarf women.
As published in The Lord of the Rings, this one is a lot more vague, simply stating that dwarf woman look alike to dwarf men in voice, appearance, and garb, but without specifically mentioning beards.
Dís was the daughter of Thráin II. She is the only dwarf-woman named in these histories. It was said by Gimli that there are few dwarf-women, probably no more than a third of the whole people. They seldom walk abroad except at great need. They are in voice and appearance, and in garb if they must go on a journey, so like to the dwarf-men that the eyes and ears of other peoples cannot tell them apart. This has given rise to the foolish opinion among Men that there are no dwarf-women, and that the Dwarves ‘grow out of stone’.
It is because of the fewness of women among them that the kind of the Dwarves increases slowly, and is in peril when they have no secure dwellings. For Dwarves take only one wife or husband each in their lives, and are jealous, as in all matters of their rights. The number of dwarf-men that marry is actually less than one-third. For not all the women take husbands: some desire none; some desire one that they cannot get, and so will have no other. As for the men, very many also do not desire marriage, being engrossed in their crafts.
The Lord of the Rings - Appendix A - 'III Durin's Folk
However, the passage used in the published text first appeared in a draft manuscript titled (titled "Notes on Chronology of Durin's Line"), and Christopher Tolkien notes that this earlier manuscript included a mention of beards.
There is no difference in substance in [the preceding draft], except for the statements that they are never forced to wed against their will (which 'would of course be impossible'), and that they have beards.
The Peoples of Middle-earth - Commentary on The Making of Appendix A - Durin's Folk
Christopher does not reproduce the earlier draft with the beards mention, and he does not speculate as to why his father edited it out. It could have been a deliberate decision to make it ambiguous, but it could have also been just a space constraint.
Two decades later, Tolkien wrote a 2 1/2 page isolated note titled 'Beards' reflecting and expanding on a letter he had sent to a fan about beards. (The original letter is unpublished.)
In this note Tolkien said "All male Dwarves" had beards, underling the word male, leading to an implication that he may have been excluding females. However this was in reference to answering the question about which specific male characters had beards, and the note as a whole was mainly concerned with the affects of elvish ancestry on human beards, not with dwarves.
A note was sent to Patricia Finney (Dec. 9/72), answering a question about beards, that mentioned some of the male characters which she and a friend did not imagine as having beards. *
[Footnote on above:] * When I came to think of it, in my own imagination, beards were not found among Hobbits (as stated in text); nor among the Eldar (not stated). All male Dwarves had them. The wizards had them, though Radagast (not stated) had only short, curling, light brown hair on his chin. Men normally had them when full-grown, hence Eomer, Theoden and all others named. But not Denethor, Boromir, Faramir, Aragorn, Isildur, or other Númenórean chieftains.
The Nature of Middle-earth - Beards
