Old Resin Beauty White: The original beauty white or white resin used by volks until they switched to pure-skin in 2003. Pale with a yellow caste to it. Dolls released with old resin beauty white are: Chris I, II & III, Licht & Leona etc.
Pure-skin LE Beauty White: the new translucsent pure-skin but similar in color to the old resin beauty white, with less of a yellow caste to it. Is very translucsent. Only used on Limited Edition dolls and One-offs. Dolls released with pure-skin beauty white are: Sasha, Sweet Dream Nana & Kohya etc.
Pure-skin FCS White: Not quite as translucscent as the LE beauty white, but with a pinker undertone that gives the pale white resin a soft glow. All FCS white orders use this resin. The only LE doll released with this resin color is MSD Lilith.
Note: (courtesy of Cassiel!) The old resin "beauty white" was quite literally that—”bihaku” in Japanese, the two kanji meaning "beautiful" and "white." The new pure skin LE-only white is also called "bihaku" so it is the new "beauty white." The link is I guess the slightly yellow undertone. Although nowhere near as prevalent in pure-skin bihaku, it still exists. It has no link to Sato—FCS white at Sato is the same colour as FCS white at any Sumika—so the term "Sato white" or "Sato snow" is a bit of a misnomer. It is simply a resin that is only used for LEs.
FCS white is quite literally just called "white." It’s not even written with the Japanese word for white (shiro) it’s written in Japanised English—"howaito" (white). It has the slightly pinkish undertone that makes it obviously and noticeably different to pure-skin beauty white.
So I guess your correct terms are "pureskin beauty white" and "pureskin white." However with all the confusion running around, I think it’s easier to stick a little extra in there and go with "pure-skin LE beauty white" and "pure-skin FCS white" to make the difference clear.
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