Like many aspects of Crystal, it’s rooted in the manga. In the manga as well as Crystal, Sailor Moon receives three tiaras during the course of the first arc.
The first one is rather basic and appears when Usagi transforms into Sailor Moon for the first time.
The second tiara was created out of necessity; Sailor Moon had attacked Jadeite with her first tiara and is was subsequently destroyed (by accident) when Sailor Mars unleashed her own fiery attack on Jadeite. Left with nothing to attack with (this was before she got the Moon Stick), Sailor Moon managed to create a new, stronger tiara by recalling her feelings for Tuxedo Mask and channeling them to making a new weapon.
This new tiara, in addition to being more ornate, was capable of absorbing moonlight to use as an attack called “Moon Twilight Flash.”
The third and final tiara wasn’t created because it was needed; rather, it seems to be the result of Usagi’s confusion and amnesia regarding her past life. The tiara is created pretty much the moment after Artemis introduces Venus as Princess Serenity, the Moon Princess. Usagi doesn’t consciously know that’s she the real Serenity, but her subconscious does; the resulting clash between them produced the tiara, which has elements of both Serenity (the crescent moon shape) and Sailor Moon (the gem and the fact that it’s a tiara and not a marking).
Of course, no official explanation is given for the third tiara, but that’s what I came up with; I think it makes a lot of sense, personally.
And the third tiara is yet AGAIN a copy of the statues and paintings of the Moon Goddess Diana…… -___- I know, I know, it is just me who is angry about copying and plagiarism, alright. XD
Can you really plagiarize from Classical Mythology, though? Myths (and their associated paintings/statues/etc) are the result of centuries of mixing and exchanging ideas; it’s impossible to pin down a direct source. Even the artists who depicted the myths built on other artists’ depictions and interpretations of how certain gods/goddesses/other figures looked.
If anything, Naoko included the tiara as a reference to Classical Mythology, something that the series has a strong connection to.
Also, I’d like to see what depiction of Diana you’re talking about! I’ve never seen something like Moon’s tiara in a Classical work.
you can’t really…plagiarize history…
and I always thought this tiara appeared as a symbol of Serenity’s arrival, like the princess has arrived and this is shown to be true by Sailor Moon’s tiara reacting. I never got “internal clash of subconsiouses” from her tiara transforming. It’s an interesting theory though.