The Elves: Chapter 38

Borges' version of elves is quite different from the Tolkien generations. He has this- "The Elves are of Nordic origin. Little in known about what they look like, except that they are tiny and sinister...In the Younger Edda, a distinction is noted between Light Elves and Dark: 'The Light Elves are fairer than a glance at the sun, the Dark Elves blacker than pitch"

Without much to go on, physically, from the text, I made something that looked sortof like the elf in my imagination. Cat eyes and pointy ears, with red around the eyes on a dark backing for that "sinister" bit. He's a small mask, but not all of them can be, need to be, or even should be, large.