I use these as an embellishment on my crowns or as an extension on my pendants. I use E6000 glue to glue them in.
Here's the specification sizes for these flares . They are inches1 3/4 (42mm) by inches 5/8ths (18mm). They are raw brass and are ready for a patina or paint. They will oxidize over a period of time, but brush up to bright golden color if you use a steel wool (size 0000) pad on them.