---
title: "Hearts and arrows viewer: meaning in gemology"
description: "A hearts and arrows viewer is a reflector scope that colors a stone by the direction its light comes from. In it, a precisely cut round brilliant shows…"
url: https://digitalgemology.com/learn/glossary/hearts-and-arrows-viewer
image: https://digitalgemology.com/img/og-digital-gemology.png?v=d224fb01
---

> Markdown copy of https://digitalgemology.com/learn/glossary/hearts-and-arrows-viewer. 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

[Glossary](https://digitalgemology.com/learn/glossary) · How we measure

# Hearts and arrows viewer

Also called reflector viewer, H&A viewer

A hearts and arrows viewer is a reflector scope that colors a stone by the direction its light comes from. In it, a precisely cut round brilliant shows eight arrows face-up and eight hearts face-down.

## In more detail

Real viewers differ in their geometry. In Kinsaku Yamashita's patented design, the white tube's rim sits 10° to 25° off the axis. The best patterns show at about 15° to 20°.

## How we measure it

Our viewer colors each ray by the angle θ between its exit direction and the viewing axis. Below 2.5° is the lens port, drawn dark. From 2.5° to under 13.5° is the white disk, which draws the arrows and hearts. From 13.5° to 90° is the red reflector; light heading away, or still inside after 24 bounces, is dark.

## Related terms

- [Hearts and arrows](https://digitalgemology.com/learn/glossary/hearts-and-arrows): Hearts and arrows is a pattern that a precisely cut round brilliant shows in a reflector viewer. Face-up it shows eight arrows, and face-down eight hearts.
- [Hearts & Arrows Scope](https://digitalgemology.com/learn/glossary/hearts-and-arrows-scope): The Hearts & Arrows Scope is a free Digital Gemology tool that simulates a hearts and arrows viewer. It shows a round brilliant's arrows face-up and hearts face-down, with one symmetry figure per view.
- [Hearts and arrows symmetry](https://digitalgemology.com/learn/glossary/hearts-and-arrows-symmetry): Hearts and arrows symmetry is the share of a hearts and arrows pattern where all sixteen halves match. Our Hearts & Arrows Scope gives it as a whole percent for each view.

## Learn more

- [Hearts & Arrows Scope](https://digitalgemology.com/about/how-we-measure/hearts-and-arrows-scope)
- [Hearts and arrows diamonds: precision you can see](https://digitalgemology.com/learn/historic-cuts/hearts-and-arrows-diamonds)

[All 328 terms](https://digitalgemology.com/learn/glossary)