Depends on where you are in Florida, the farther south you go the more chances to find stuff year round as the water is warmer and people stay in the water longer.
Rip currents, especially on the Atlantic open up huge holes and make it possible to find old rings and jewelry that has been under seveal feet of sand for a long time. You have to work the hole when it is open as it will be covered up fairly quick.
Last year in Daytona we found a huge hole that was opened up by a rip tide, Hole was at least 50 yards long and 20 to 30 yards wide. You would walk out mid calf, suddenly drop to waist to chest deep then back out to less then knee deep. While talking to other hunters at the GSBSO we talked about the hole and found out at least another 22 gold rings came out of the same hole that we took and saw at least 16 come out in one hunt. We were bringing up chunks of clay so that tells you how much sand had been removed by the rip current.
If I knew then what I know now, I would have rented a room, called in sick, and hunted that hole for days till I couldn't walk. Hole was open for about 2 weeks before it sanded in, besides the gold jewelry we were finding lots of old silver coins also.......