[Female dwarves 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.
(Yes yes, JRRT waffled on this. But come on! This is good lore, let’s keep it)
Tolkien went back and forth on this, as he did with many things
Lord of the Rings, Appendix A: Durin’s Folk
(Yes yes, JRRT waffled on this. But come on! This is good lore, let’s keep it)