Generally one of the sucker tube setups with various size tips to get into cracks. If shallow water, then add long shank common screwdriver, crevis tools, etc, Also a bucket to dump your sucker into, and pan of course. Bigger suckers can keep a sluice going when you hit the big cracks.
Do a search on gold suckers or hand dredge and you will turn up many on the market, and they are fairly easy to make yourself as well.