The first happened last Friday in Jackson Heights, Queens and in less than 48 hours, the second attempted robbery happened in Bay Ridge, Brooklyn.
The jewelry shop owners are sharing their concerns.
The thieves made a b-line for the jewelry store in broad daylight using hammers to break the window.
A startled worker inside at the time ran out from behind the counter to protect a little girl who was playing.
"If anything - the first thing you do is push here," jewelry store owner Ibrahim Salem said.
Salem said the worker, his niece, pushed a panic button to alert the police, but the attempted smash-and-grab was quick.
"He has limited time - maximum 30 seconds - he boom, boom, boom, boom, quickly, quickly, quickly, run," Salem said.
Fortunately for the jewelry store, the owner in Bay Ridge was one step ahead of the game, having already installed double pane, bullet-proof glass windows.
The hammer used could only shatter, not break through.
Just as quickly as the thieves showed up, they ran off empty-handed.
This is the second time Salem has outsmarted thieves, snapping a picture of their license plate.
In 2018, his other 'Pyramids Jewelry' store was broken into.
"I run to him like a tiger," Salem said.
Salem charged at a different thief who had no idea the owner was sleeping in the back of the store.
Salem scared him off then, still wishing now other youngsters would smarten up.
"Somebody supposed to tell them - if you work, hard work, or if you go to school - you'll be a doctor, you'll be a lawyer, now you lost your life," Salem said.
Sunday's failed burglary attempt in Brooklyn came only two days after another heist that was successful in Jackson Heights, Queens.
Police say the thieves similarly used hammers to steal $800,000 worth of jewelry from Abid Jewelers.
"I just opened the door - and after they run," Abid said.
Police believe the same crew is also responsible for destroying Salem's front window.
"It costs 2,800 dollars," Salem said.
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