You can clean your dichroic glass necklace with glass cleaner. Pat, don’t rub, it dry with a soft cloth and then buff with a chamois.
Wiping it clean with a water-moistened cloth is the recommended way to care for your onyx jewelry. The porous stones tend to absorb chemicals, so avoid soap, ammonia and ultrasonic cleansers.
Sterling silver should be stored in an airtight container with a soft lining. Cleaning with soap and water and buffing with a soft cloth will keep your sterling silver shiny as new. Avoid exposure of your sterling silver to abrasive cleansers and bleach, which may cause discoloration.