Study for the DCA Gemology Test. Utilize flashcards and multiple-choice questions, each question offering hints and explanations. Prepare effectively for your exam with confidence!

Multiple Choice

What is the typical refractive index range for diamond?

Light slows down in a material in proportion to its refractive index, and a higher index means light bends more when it crosses a boundary. Diamond sits at a very high index in the visible range, about 2.417 to 2.419, with only a tiny variation across wavelengths. This means light travels roughly at c/2.42 inside diamond and is bent strongly at facet junctions, enabling many internal reflections that produce the stone’s characteristic brilliance and fire. The other ranges don’t match diamond: common glass is around 1.5–1.6, 1.0–1.2 is near air or water, and 2.65–2.70 is higher than diamond’s typical value.

Light slows down in a material in proportion to its refractive index, and a higher index means light bends more when it crosses a boundary. Diamond sits at a very high index in the visible range, about 2.417 to 2.419, with only a tiny variation across wavelengths. This means light travels roughly at c/2.42 inside diamond and is bent strongly at facet junctions, enabling many internal reflections that produce the stone’s characteristic brilliance and fire. The other ranges don’t match diamond: common glass is around 1.5–1.6, 1.0–1.2 is near air or water, and 2.65–2.70 is higher than diamond’s typical value.