I made this for a friend a few months ago using a dremel rotary carving tool.

This is the inside which hides a music box movement that plays 'Romeo and Juliet'. I used chalk to color the knot and then a couple coats of polyeurethane.

The top. I carved the knot and then stained it. After a couple of days, I coated the stained parts with turpentine then sanded it off. This takes off the avaliable layer of stain, leaving the resting that had seeped into the carving. After the rest had been carved I stained the whole thing again making the lines even darker.