What is the color of Gollum's skin?

Question

In The Hobbit, Gollum is described as being

as dark as darkness, except for two big round pale eyes in his thin face.

This has always led me believe that Gollum's skin is very dark, probably because of his ~500 years spent underground. I have assumed that his appearance is so different in the films because pale skin works better visually (a dark-skinned Gollum in a dark cave is nearly impossible to see). However, this article on Tolkien Gateway says that Gollum does indeed have pale skin.

Where is Gollum actually described as having pale skin in Tolkien's works? Is the Tolkien Gateway information correct, or is Gollum dark-skinned as I've always assumed?

Answer 1

There are a few times where Gollum is described as white or pale (emphasis mine):

Frodo was just yielding to the temptation to lie down again when a dark shape, hardly visible, floated close to one of the moored boats. A long whitish hand could be dimly seen as it shot out and grabbed the gunwale; two pale lamplike eyes shone coldly as they peered inside, and then they lifted and gazed up at Frodo on the eyot.

^{Fellowship of the Ring Book II Chapter 9: "The Great River"}

For a moment he might have paused to consider Gollum, a tiny figure sprawling on the ground: there perhaps lay the famished skeleton of some child of Men, its ragged garment still clinging to it, its long arms and legs almost bone-white and bone-thin: no flesh worth a peck.

^{The Two Towers Book IV Chapter 3: "The Black Gate is Closed"}

Tolkien himself clarified Gollum's complexion in a late manuscript, which as far as I know is unpublished aside from excerpts in works of Tolkien criticism (such as A Reader's Companion), where he emphatically states that Gollum is pale, and suggests that the descriptions of him being "dark" come from his clothing and a tendency to being seen in low-light conditions:

He is often said to be dark or black. At his first mention [in The Hobbit] he was 'dark as darkness': that of course means no more than that he could not be seen with ordinary eyes in the black cavern - except for his own large luminous eyes; similarly 'the dark shape' at night [The Lord of the Rings, Book II, Chapter 9]. But that does not apply to the 'black (crawling) shape' [in Book IV, Chapter 1], where he was in moonlight.

Gollum was never naked. He had a pocket in which he kept the Ring....His skin was white, no doubt with a pallor increased by dwelling long in the dark, and later by hunger.

^{A Reader's Companion Book IV Chapter 1: "The Taming of Sméagol"}

Answer 2

He is described by the orcs outside Shelob's tunnel as a:

You must have seen him: little thin black fellow; like a spider himself, or perhaps more like a starved frog.
_{The Two Towers - Book IV, Chapter 10: The Choices of Master Samwise}