In fifteen years of fitting out jewelry stores we have seen the same pattern again and again: the same inventory sells noticeably faster under the right light. Color temperature, beam angle and lamp position decide whether a diamond sparkles or looks flat.
Five setups cover almost every case. Use 3000K warm white for gold jewelry and 6000K cool white for diamonds and platinum. Fit narrow-beam spots on hero pieces so they catch the eye from the entrance. Add vertical LED strips inside wall cabinets to light pendants evenly. Put edge-lit glass decks under white gold to lift its cool tone. And keep overall brightness low around the showcases so the lit displays stay the brightest thing in sight.