---
title: "Star and lower half lengths: lesson quiz"
description: "Five questions on “Star and lower half lengths”, lesson 6 of Digital Gemology's Anatomy of a diamond course, in a new order every time, with an explanation for every answer."
url: https://digitalgemology.com/skool/quiz/anatomy-of-a-diamond/star-and-lower-half-lengths
image: https://digitalgemology.com/img/og-digital-gemology.png?v=d224fb01
---

> Markdown copy of https://digitalgemology.com/skool/quiz/anatomy-of-a-diamond/star-and-lower-half-lengths. 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

[Anatomy of a diamond](https://digitalgemology.com/skool/quiz/anatomy-of-a-diamond#lessons) · lesson 6

# Star and lower half lengths

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

Five questions on lesson 6 of Anatomy of a diamond. 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: What does star length measure?
  ### Show the answer
  **b**: A percentage of the distance from the table edge to the girdle.
2. Question 2: A stone has a 90% lower half length and Excellent everything else. What's the best grade it can get?
  ### Show the answer
  **b**: 90% is outside 70–85% but inside the Very Good range.
3. Question 3: Why would a cutter paint or dig out the half facets?
  ### Show the answer
  **b**: Painting and digging out trade looks for weight.
4. Question 4: The T73 and T105 both read 100% symmetry in the H&A Scope but show different hearts. Why?
  ### Show our answer
  Symmetry says the eight hearts match; the T105's extra rows of lower facets change what each heart looks like.
5. Question 5: Can a star length of 30% take a stone below Good?
  ### Show our answer
  No. 30% is outside the Very Good range (40–70%), so on its own it limits the stone to Good. But GIA's tables allow any star length at Good, so it can't pull the stone lower.

## More

- Next: [Lesson 7, The girdle](https://digitalgemology.com/skool/quiz/anatomy-of-a-diamond/the-girdle)
- [The Anatomy of a diamond quiz](https://digitalgemology.com/skool/quiz/anatomy-of-a-diamond), on the whole course
- [All Anatomy of a diamond lesson quizzes](https://digitalgemology.com/skool/quiz/anatomy-of-a-diamond#lessons)
- [Anatomy of a diamond: all the lessons](https://digitalgemology.com/learn/diamond-anatomy)