Step 1: Tools & Materials
Dentist drill bit (ask your dentist for a couple of left overs or buy some from a dental supply store)
Round nose pliers
Sea glass (1/4 inch thick or less - the thinner the easier)
Small shallow bowl (not glass or china)
Cup of water
German jewelry wire (for bail), or large jump ring, or small silver paper clip
Warning....you must press down on the glass very hard with your fingers, and hold the sea glass VERY FIRMLY so it doesn't move at all while you are drilling it. If it does slip, the glass can fly out and hit you, shatter and hit you, or jerk your finger into the Dremel and...yes, hurt you. I've done all three over the years and so I've learned to use great caution whenever I drill sea glass. Just exercise caution and be sure to wear your safety glasses (rubber finger guards wouldn't be a bad idea either if you have them - I've never used them myself though.
Use your left hand (if right handed) to press and hold down your sea glass VERY firmly so it won't move at all, making sure you leave enough room for the drill bit.
Begin drilling the hole by pressing the drill bit firmly (but not forcefully) onto the glass making sure you pull back pressure and pull the bit all the way out every 5 seconds so water can flow back into the hole and the glass can cool off. After a couple of seconds carefully put the drill back into the hole while at full speed and press down again for another few seconds. Continue this pulsing type action (3-5 seconds drilling 2-3 seconds rest) until you make it all of the way through your piece of glass.
If you've been at it a while and not sure how much progress you're making, turn your Dremel off and pull your sea glass out of the water and hold it up to a light. You should be able to see the hole through the side and be able to determine how much farther you have to go (see second picture). It is important that you don't push too hard (especially near the end) because that will cause the glass to break (I've broken several beautiful pieces being impatient and that is very frustrating).
When the drill makes it through the glass, quickly pull back (without letting go of the glass) so you don't drill through your bowl or over drill the glass. Turn your Dremel off and take your newly drill sea glass out of the water and admire your handiwork!
Note: If you plan on drilling multiple pieces of glass you will want to change to a new bit each time. Glass is tough on the bit and if you try to drill with an old bit you are more likely to have to press harder and brake your beautiful sea glass. Rule of thumb, new piece - new bit.
If you do fashion your own bail, make sure that you do the bulk of your wire twisting before you slide it through the hole in the sea glass so you don't put too much stress on the rather thin edge of the glass. If you try to bend a heavy gauge wire using the sea glass as a pivot point, the sea glass may break. I have found that using two pliers for final adjustments once the bail is threaded through the hole works best; one to anchor and hold the bail firmly while the other bends the wire to the desired position - keeping the bulk of the tension/pressure off of the glass. Get creative with your bail - it doesn't have to look like mine. There are countless designs that you could use. Just think about how you want to ultimately attach the sea glass to your necklace and what look would compliment the finished piece of jewelry and go from there.
In my example, after forming the bail I then threaded the big end through the bottom center hoop of a 18' length of chain and finished it off with a lobster claw and jump ring on each end. If you want to make this even simpler, you can buy a finished chain necklace complete with end clasps (such as lobster claw and jump ring or a toggle clasp) at most craft stores or jewelry departments in other stores, and then just add your stunning sea glass pendant to the finished necklace making it a gorgeous new piece of custom jewelry!
I hope you have fun making beautiful sea glass jewelry that you can wear proudly this summer. There's no better way to display and enjoy those rare and precious mementos from the shore!