Yehuda.com

Yehuda sells AI-powered devices that identify gemstones, including the Sherlock AI and Watson AI models. Its Sherlock Holmes 4.0 is also offered, and the company says it detects newer types of synthetic diamonds that older units may miss. Cubic zirconia shows a distinctive pink fluorescence that the system uses to tell it apart.

The devices connect through a special cable rather than wireless or Bluetooth, and a monthly subscription of $12.50 applies. Delivery is quoted at four to six weeks. Owners of Sherlock Holmes 1, 2 or 3 units can trade them in for $2,000 toward a Sherlock Holmes 4.0. Calls can be placed to the company's listed phone number.