Tolkien's Mistakes

[Lalwendë]

I've been meaning to post this possible mistake relating to the weapons of Legolas for some time - it was spotted by my boss, who then had me look up the references to exactly what weapons he had and when. So...is this a mistake?

Bk2 Ch3 - Legolas as he leaves Rivendell:

Legolas had a bow and a quiver, and at his belt a long white knife.

Bk2 Ch8 - Legolas as he leaves Lothlorien:

To Legolas she gave a bow such as the Galadhrim used, longer and stouter than the bows of Mirkwood, and strung with a string of elf-hair. With it went a quiver of arrows.

Note: Galadriel doesn't give him a new knife.

Bk3 Ch6 - Legolas entering Meduseld:

Then Legolas gave into his hand his silver-hafted knife, his quiver, and his bow. 'Keep these well," he said, 'for they come from the Golden Wood and the Lady of Lothlorien gave them to me."
Wonder came into the man's eyes, and he laid the weapons hastily by the wall, as if he feared to handle them. 'No man will touch them, I promise you," he said.

Is this a mistake, or was Tolkien interchanging silver and white as descriptive terms - in that silver can often look almost white when dulled?