Mr. Bromeliad made these as gifts for his family from bits of stone and granite we picked up on the beach while in Thailand. Since most of the stones were granite and thus hard as a rock, he couldn't drill a hole in them very well. His workaround looks like a pretty good imitation of electroplating but doesn't require much in the way of tools.
To make similar no-hole-required pendants from raw stones or crystals, you will need teardrop or flat-backed stones, solid-core solder (no acid flux) that you can get at a hardware store, a heat-resistant cup (Mr. Bromeliad used a large plumbing end cap), drill and matching chain.
First, glue a bail to the flat side of each stone and allow to dry. See this post on how Mr. Bromeliad made bails from jack chain.
Drop some solder into your cup and heat over the stove until it melts.
Them let the solder cool a little. Try dipping in the stone, bail side into the solder.
Getting the solder to stick is tricky. If the solder is too warm, it will roll right off the stone. Same if the stone is too cold. Just about the time you are ready to completely give up, they will start to stick nicely. (Using flux did not seem to help.)
You want the solder to cover up the bail and part of the end of your stone.
Allow the solder to cool. Then use a drill to gently open up the hole in the bail.
String your pendants on matching chain (silver in this case.)
Place in a fancy gift box.
Impress all your nieces.