Hello,

Number one is indeed a standard safety chain for a bracelet. Standard
sizes are 4 or 5cm.

Number two is a safety chain for a brooch. It looks like the pin is
not sharp though in the pic... it might just be the photo, but
sometimes they are blunt so the sharp point doesn't split and fray the
fabric (kind of like how you use a ball-point needle when sewing knit
fabric). You can file it to a point if you want to. The other end
attaches to the back of the brooch and the safety pin is usually
hidden under the brooch.

Number three is a brooch pin.

Number four : The one on the right is definately a tie tack back or
clutch. The bar is inserted in to a button hole behind the tie as a
safety measure. The one on the left could be a similar thing with the
bar missing or.... does it have a hole in the other side? If not, I'm
assuming it also a safety chain for a tie bar and the 'button' goes in
a button hole behind the tie. If the other side of the 'button' is
plain or has a pattern, it could avtually be a decorative button that
is missing a safety pin on the other end. Sometimes these are worn in
a top button hole on a shirt or even the little button holes on some
collars and the chain would have a safety pin on the other end (like
the one on the brooch safety chain) which is hidden inside the shirt
or under the collar. Of course, if it's meant for the collar hole,
there should be two of them...

Number five is a bit of a mystery... looks to me like something that
was made for a specific item. Looks like one side of a hinge... sorry,
can't help with that one.

Tracy