Unintended color zoning in gemstones refers to?

Unintended color zoning in gemstones refers to visible face-up color zoning that the cutter was unable to conceal. This phenomenon occurs when there are natural color variations within the gemstone that the cutter did not anticipate or manage effectively during the cutting process. While some color zoning can be intentionally incorporated into the design of the gemstone, unintended color zoning is typically seen as a flaw, as it can detract from the overall beauty and uniformity of the stone when viewed from the top. The inability of the cutter to hide these color variations indicates a lack of control over the aesthetic outcome during the cutting and polishing stages, making it a distinct characteristic of unintended color zoning.