Which knot is this?

Question

I am trying to figure out which knot this is. Is it a prime knot or a composite knot?

If I am counting correctly, there are 8 crossings in this image. Is this knot 8_16 shown here?

edit: I am starting to think this is 8_18.

P.S. This the cover of Agalloch's The Serpent & The Sphere Album.

Answer 1

This is a torus knot, namely T(4,3), also known as $8_{19}$.

Being a (nontrivial) torus knot, it is prime.

Answer 2

(Troposphere has already answered this question, but I thought I'd show off a tool you can use to identify knots.)

KnotFolio is an online program where you can draw knots, and if it's prime and has few enough crossings, in most cases it can identify it.

I quickly drew the general path of the knot and used the crossing change tool until it matched your knot:

And then it identified the only possible prime candidate:

Clicking on the 8_19 link, we see that one of the images in the gallery matches the knot more or less exactly:

So it's identified!

The common name for this knot is the true lover's knot.