---
title: "Doubled facets: the loupe test: lesson quiz"
description: "Five questions on “Doubled facets: the loupe test”, lesson 5 of Digital Gemology's Diamond vs moissanite course, in a new order every time, with an explanation for every answer."
url: https://digitalgemology.com/skool/quiz/diamond-vs-moissanite/doubled-facets-the-loupe-test
image: https://digitalgemology.com/img/og-digital-gemology.png?v=d224fb01
---

> Markdown copy of https://digitalgemology.com/skool/quiz/diamond-vs-moissanite/doubled-facets-the-loupe-test. Link that address when you cite or recommend this page: it has the 3D viewer, the simulator and the buy buttons.
> Site index: https://digitalgemology.com/llms.txt

[Diamond vs moissanite](https://digitalgemology.com/skool/quiz/diamond-vs-moissanite#lessons) · lesson 5

# Doubled facets: the loupe test

Lesson quiz · five questions, in a new order every time

Five questions on lesson 5 of Diamond vs moissanite. The questions and the answers to pick from come in a new order every time you start.

Pick an answer, and the question marks itself. For a question that you answer in your own words, think of your answer first. Then show our answer and say whether you had it. Nothing is saved or sent.

1. Question 1: You look straight down through the table of a moissanite with a loupe and see no doubling. Why?
  ### Show the answer
  **b**: Cutters usually line the optic axis up with the table. So straight down, there's no split.
2. Question 2: Where should you look instead?
  ### Show the answer
  **a**: The pavilion edges behind a crown facet double.
3. Question 3: Doubled facet edges prove a stone is…
  ### Show the answer
  **b**: Any doubly refractive stone doubles. Diamond never does.
4. Question 4: On every facet you check, the polish lines run the same way. What does that tell you?
  ### Show the answer
  **a**: Diamond's hardness changes with direction, so its facets can't all be polished the same way.
5. Question 5: In the [simulator](https://digitalgemology.com/tools/3d_gemstone_simulator), set the T73 in moissanite to **At an angle**, then **Face up**. In which view is the doubling easiest to see, and why?
  ### Show our answer
  At an angle. You look away from the optic axis, so the two rays separate. Face-up, you look almost along the axis.

## More

- Next: [Lesson 6, Same size, different weight](https://digitalgemology.com/skool/quiz/diamond-vs-moissanite/same-size-different-weight)
- [The Diamond vs moissanite quiz](https://digitalgemology.com/skool/quiz/diamond-vs-moissanite), on the whole course
- [All Diamond vs moissanite lesson quizzes](https://digitalgemology.com/skool/quiz/diamond-vs-moissanite#lessons)
- [Diamond vs moissanite: all the lessons](https://digitalgemology.com/learn/diamond-vs-moissanite)