Gold rings with open cracks in the band, or open gold earrings will respond like a bottle cap on VLF metal detectors, even when using a minimum amount of discrimination.
A less experienced beach or water hunter, may decide the piece of jewelry has not got a two way repeatable response and decide to pass on scooping the broken signal.
This 1932 18K gold masonic ring with a 3/4 carat diamond is one of my favorite "Bottle cap" signals, which I obviously stopped to scoop up a few years ago.
I recently went water hunting at the beach I recovered this old beauty, it is a place that I rarely walk away from without recovering old jewelry or coins.
I hardly ever see other people metal detecting at this place, and even fewer people in the water swimming. It is just a great place to find old jewelry and coins from when the beach used to be popular.
Because most of the stuff I recover here is old, targets are usually deeper and tend to be encrusted in coral.
I never did clean this ring all the way up, just in case I broke it and I like it the way it is.
It is very easy to get set in your ways when you first start metal detecting, especially when you do start finding jewelry and coins.
You could say that you learn to differentiate between trash and treasure, but many good targets can often mimic bad targets, especially if they are encrusted in sand or coral.
Gold class rings have plenty of nooks and crannies around the embossing for coral or sand to become attached to after spending a long time in the water or on the lower beach.
That is exactly what I thought this masonic ring was before the coral dropped off after a long soak in lemon juice.
Try not to get too wrapped up with basing your scooping decisions on hearing a two way repeatable signal.
Remember, even the best means of discrimination is only accurate to a certain depth.
If you have a display screen with a depth indicator, scoop a few more of those iffy signals showing deep readings.
They could be broken rings, open or unusual shaped earrings, or bottle caps, but it is always nice to know for sure.