Stuffed toys of the left and right trefoil knots. Despite being mirror images, there is no way to deform one trefoil into the other, so they are genuinely different knots, although it takes quite a lot of ingenuity to find a knot invariant which can tell them apart(I think the Jones polynomial does it?).

• I didn’t keep notes when I wrote this pattern, and it was quite a while ago, so it’s possible I’ve got this all horribly wrong. So, y’know, be warned. And if you do spot something let looks wrong, let me know. *