This is a wonderfully simple, yet elegant way to wear a false or detachable collar. These are made with size 20 thread and a size 10 steel crochet hook. I used the Venetian Lace square pattern that is available on my blog here: https://crochetthread.wordpress.com/2011/09/25/venetian-tile-piano-runner-project/
The pattern changes I made were: 1. I added an extra join at the interior of the back for a more rounded corner. 2. For the larger collar, I filled in the center grid with closed mesh. 3. I added pearl enhancer pendants to the front join.