GT Advanced Technologies Inc., has announced the release of a case study that details the findings of a series of blind material studies conducted to evaluate the impact of sapphire color on the LED manufacturing process. The studies demonstrated that all sapphire, regardless of source, exhibits color at the core level, that the pink hue of GT Advanced Sapphire Furnace (ASF) material is not indicative of impurities, and that pink ASF sapphire doe...