Reference: Colours
Hastings
The colours named in OT and NT, as in other ancient literatures, are few in number, and of these several are used with considerable latitude.
1. White as the colour of snow in Isa 1:18, of the teeth described as milk-white (Ge 49:12), and of horses (Zec 1:8; 6:3,6); also of wool (Re 1:14)
See Verses Found in Dictionary
He answered,
And he directed them all to sit down in parties on the fresh grass.
and his clothes shone whiter than any earthly bleaching could make them.
And they dressed him up in a purple cloak, and made a wreath of thorns and crowned him with it,
And the soldiers made a wreath out of thorns and put it on his head, and put a purple coat on him, and they marched up to him,
You show that you are a letter from Christ delivered by me, written not in ink, but in the Spirit of the living God, and not on tablets of stone, but on the human heart.
His head and hair were as white as white wool, as white as snow; his eyes blazed like fire;
When he broke the third seal, I heard the third animal say, "Come!" And there I saw a black horse, and its rider had a pair of scales in his hand,