Problem
The colors for some items are buggy, or do not match their descriptions, and should probably be changed.

[1] Crystal daggers and crystal large shields show up as black (over a black background), instead of white as other crystal items.


[2] Pink potions are orange on the floor, and they should be pink (duh :P).
[3] The obsidian sceptre, black javelins, obsidian javelins, both black rune-covered daggers, and the jet-black battle axe are #BBBBBB on the floor, while they should be #777777 as other black/dark-colored items.
[4] Marble amulets are #BBBBBB on the floor, but marble wands and rings are #777777. I feel both should be #BBBBBB.
[5] Coral necklaces are #AA00AA on the floor, but coral rings are #FFFFFF. I feel both should be #AA00AA.
[6] Crystal helmets (commonly helms of mental stability) should be white like other crystal items, not blue.

Also:
[7] Weapons with "color" pre/suffixes thrown by monsters (e.g. an orcish spear of lightning thrown by an orc scorcher, or a red battle axe thrown by a gnoll) are shown with their regular color when they're in the air, and change to their real color after they land on the floor.

These fall into the suggestions realm:
[8] Ambers (the gems) are #995500 on the floor. They should be #FF7E00 as that's the correct amber color.
[9] Amber rings, amber amulets and amber potions are #DDDD00 on the floor. They should also be #FF7E00.

How to reproduce it
See above.

Notes
Here's a nice site to transform hex values into actual colors.