I would just soak them all in a container with soap, you'll only have to dry them all one by one.

I did a bunch of the same size, in a colander, in the sink, cuz I don't have a dishwasher.

by the time you mosaic, you'll be handling them anyway, so, I just wanted to get the surface dirt off, to start with.
a sprayer is always helpful..

Becky ;(*_*);

Someone here posted that you could smooth the edges by filling a miracle whip container 2/3 full with pieces, covering with water and adding a "tad" of dish soap. Then shake. Someone else said they shook while watching tv during the commercials. Seems like you could rinse in a colander after and kill two birds with one stone! I'm going to try this with my broken dishes but I haven't broken them yet.
kathy

A suggestion would be to clean one pc, and use it to scrape the sides of all the others, it may be time consuming, but what you are doing is taking the sharp edges off so you can handle them anytime without getting cut. Much safer, therfore enjoyable. It's something I learned from a glass shop I worked at. I thought I needed a grinder or carbodium stone to take the sharpness off the edges, but just running the glass edge to edge works good too!!!

The best way that I have found to clean small pieces is to use a large strainer, like for spaghetti, and place it on the bottom rack of your dishwasher and run it through on the HEAVY CLEANING setting. Each peice will be sparkling clear when it's done.

Another way if you don't have a dishwasher. Put them in a bowl add just enough water to cover and add a couple of efferdent denture tablets and let them do the work. Put in colander, rinse with hot! hot! enen boiling water and wa la!!!! Let set for an 1/2 to and hour and they will air dry themselves. Ot lay on towel to dry. Works great and you never have to touch them. Cathy

Depending on how many pieces you have, get a container big enough to hold them-ice cream bucket, what ever with a lid and shake them for a bit. I have a 30 min drive to work, so I set it in the floorboard of my car. a couple drives and its clean and the edges are smoothed off. rinse off with a sprayer and just lay out on a towel to dry. If I have tiles I have cut I use a jar and throw it in the floorboard and usually one trip does it. and sometimes I just sit and shake the jar for a bit. and they are so sparkling clean!
Any of these ways should work great, just pick one you like!