- box clasp
- barrel clasp
- magnetic clasps,
- others too hard to categorize ;-)
They are also often the style most likely to have a stone or pearl set into them. Finding a clasp that matches or coordinates with your creation is a score - it make the finished piece look very polished and well put-together.
Sometimes, they have one or even two "safety catches" - hook type levers that swing closed over a post to create an even more secure fastening.
The barrel clasp is one that I put in a category by itself - I personally loathe these. You may have better luck with them - but I have lost more jewelry to these nasty little b-----s than any other style. They screw together - which is fine, but while you are wearing them, as they roll up and down on your skin, they tend to unscrew - and fall off. I wouldn't suggest using them on any piece of jewelry that you cared about unless you included a safety chain.
A safety chain is simply a short length of chain that permanently attaches one end of the jewelry to the other. For a bracelet - it can be very short - it just needs to be long enough to allow you to get your hand through the bracelet - and then do it up. It then hangs as a loop while the bracelet is closed - but if it accidentally comes undone - then it will retain the bracelet - hopefully long enough for you to notice and retrieve it and refasten it. This is a good option on very expensive pieces. It is less common on necklaces - as you would have to leave it fairly long on a short necklace - so that you can still slide the necklace on over your head - and messing up you hair in the process.
Magnetic clasps have a magnet inside them that keeps them closed. Magnets stick to each well when being pulled straight out - but can be slid apart to the side fairly easily - so the better magnetic clasps have a small nub or shelf that prevents them from sliding sideways. To open these - pry a fingernail into them, and twist and lift them open. They can be great for stiff fingers that find struggling with a clasp difficult. However - on bracelets - in the winter - they are frequently not up to the task of overcoming the resistance of being pulled off along with parkas, sweaters, and other cold weather gear. In this case - a safety chain is a very good idea, but check first that the chain does not have a steel base - hold it up to the magnet. It's very annoying to have the chain stick to the clasp all the time. (At least it keeps it out of the way.) I personally find working with magnetic clasps annoying - as anyone who has listened to me swear at them sticking to the cutters, pliers, tools, etc. can attest.
And - in case you aren't aware - NEVER combine a magnetic clasp with a pacemaker.
We've seen the snap clasp - a simple snap closure - borrowed from the garmet industry - most often seen on heavily beaded items.
These Snap clasps seem to have a common ancestor with the snap closure.
Tube clasps are related to the box clasp - with a tube-shaped hollow box, and a frequently spring loaded rod that slides inside. These sometimes have a magnet as well to make them more secure. These are wonderful multistrand clasps and are quite easy to put on.
This sliding safety clasp is a hybrid between the box clasp and the hook and eye. Like the box clasps - it has a hollow compartments and a spring loaded lever - but it also hooks around a post, so that if it opens up - it does not fall off.
This fold over clasp folds over a ring or loops, and relies on fitting down snuggly over itself to stay closed. Something similar to this is seen on quite a few watch bands.
Alternately - some fold over clasps rely on a magnet to help them stay closed.
This particular clasp had a very innovative design - one of the petals slots into the centre and rotates 90 degress to make a closed clasp that is virtually undetectable.
And finally - these interlocking pieces fit together like some sort of puzzle pieces. Clever designs like this always attract and delight me! Even more so when they actually work!
That about wraps it up for clasps - everything you ever wanted to know, and a whole whack besides. ;-)