The casino industry are using the RFID - Radio Frequency Identification. Some chips especially the higher value - from $100.00 to Million $ casino chips are embedded with "microchip".
The $1.5 M robbery at the Bellagio Casino was foiled by the RFID chips.
At the Taj Mahal Casino - two guys, in the wee hours in the morning grabbed and run through the front doors with "plastic bag full" of high value chips. The night shift manager - ordered all chips in all tables of that specific rack records - were sent back to the cage cashier and replaced by the secondary rack chips and the business went on. By about 10:00 am reports came in that the entire lot was recovered.
A box person and a waitress wife were handcuffed by NJ Commission DGE - nipping and clipping chips. Believe to be going on for a long while. The mistake was the wife regularly cash the chips before going off duty - the eye in the sky - with the floor surveillance were on their jobs. Lesson crime does not pay, they paid prison time and disgraced.
HOMELAND SECURITY has more advanced RFID than what the casinos has.
Personally we almost got into "big trouble" at Terrible Casino - a security guard approached us and said to one in group, politely "Sir, I think you forgot something inside the casino" Went back inside, took out few not all chips, exchanged to value chips.
Recently tourists in Beijing, China were detained because one "item" mixed up in the group paid for but was not scanned by the cashier. You cannot be too careful not to mind conscious or unconsciously do inside a store.