A) For coloured stones Top & Bottom Halogen Light Identify specific stones and quality Check Natural and synthetic B) For Gemstones & diamonds One halogen & one white light Identify stones and inclusions Quality ogf gems & jewellery Professional Gem Grading Microscope Hi - Power Imported lenses 67x / 72x power zoom Dark Field / White Field Inclinable head gives Neck Comfort Rotatable 360 neck comfort Wild Field 40x power Dark Field / Bright Field Prefered by gemological institutes