Judging by Blass’s tweet, the blue color we saw in images of S26 Ultra SIM card trays will be branded Sky Blue, while the purple (apparently the Ultra’s “hero” color) will be called Cobalt Violet. Silver Shadow is presumably a shade of gray, while Pink Gold should be similar to the S25 Ultra colorway of the same name, which is kind of a pale peachy color (though on the S25, it’s technically “Titanium Pinkgold”). Blass didn’t include images in his post.
This all lines up neatly with purported leaked S26 Ultra wallpapers we saw in December, which feature the same six colors. Samsung currently offers the Galaxy S25 Ultra in a total of seven colorways, three of which are exclusively available when purchasing the phone through Samsung.com.