When selecting a diamond, one of the most important qualities to consider is its light performance, which is how well a diamond handles and reflects light. A key tool in assessing a diamond’s light performance is the ASET (Angular Spectrum Evaluation Tool), developed by the American Gem Society (AGS). This tool provides invaluable insight into a diamond's brilliance, fire, and overall visual appeal. In this article, we’ll explore the ASET tool, how it works, and how it can help you choose a diamond that excels in light performance.
What is the ASET Scope?
The ASET Scope is a simple but powerful device used to evaluate how well a diamond handles light. It works by projecting light through a hemispherical tool, color-coded to represent different angles of light entering and exiting the diamond. This allows you to see how light is distributed across the diamond, revealing areas of brilliance and fire, as well as potential issues like light leakage.
The ASET tool is a key component of the AGS’s light performance grading system, which uses advanced technology to measure a diamond's cut quality based on its ability to return light. By using the ASET framework, experts can analyze how effectively a diamond’s facets interact with light, helping to predict the diamond's overall brilliance and visual appeal.
How Does the ASET Scope Work?
The ASET Scope works by using a hemisphere with different color zones to reflect light coming from various angles. The key color zones are:
-
Green (0-45 degrees): Light that enters the diamond from a low angle.
-
Red (45-75 degrees): Light entering from a moderate angle.
-
Blue (75-90 degrees): Light entering from a higher angle.
These different light angles affect the diamond’s overall performance. For example, red zones typically indicate optimal brilliance, while blue areas show how light is blocked by head shadow, which creates contrast and scintillation. The green and red areas are ideal because they indicate areas where light is being captured and reflected, contributing to the diamond's overall sparkle and fire.
An ASET map showing a well-cut diamond will generally have a preponderance of red, a small amount of green, and a symmetrical blue pattern with little to no light leakage. This indicates a high-quality diamond that returns light effectively and displays vibrant fire and brilliance.
Why ASET Matters for Diamond Selection
ASET’s light performance analysis is invaluable when choosing a diamond because it provides a visual map of how light interacts with the stone. This helps you make informed decisions about which diamonds offer the best brilliance, fire, and scintillation, rather than relying solely on subjective measures of visual appeal.
-
Brilliance: How bright the diamond appears when light is reflected back to the eye.
-
Fire: The colorful flashes of light that appear as the diamond moves, giving it a vibrant, fiery look.
-
Scintillation: The sparkle or "dancing" effect that occurs when the diamond is moved in the light.
A diamond with optimal light performance, as shown through the ASET tool, will have a good balance of these qualities, ensuring that it catches and reflects light beautifully from every angle.
How to Use the ASET Scope
The ASET Scope is typically used by jewelers and gemologists, but it can also be helpful for consumers looking to assess a diamond’s performance. The ASET tool can be used with round, princess, oval, emerald cut, and even fancy shapes of diamonds. For round diamonds, the ASET tool is especially helpful because it shows how the facets interact to create brilliance and fire.
The ASET map itself provides a wealth of information, showing the following:
-
Symmetry: How well the diamond’s facets are aligned and how evenly light is distributed.
-
Light leakage: Areas where light escapes the diamond, reducing its brilliance.
-
Contrast: The balance between light and dark areas, contributing to scintillation.
By using the ASET Scope, you can easily identify diamonds with poor light return or those with excessive light leakage, helping you avoid diamonds with compromised performance.
Benefits of ASET-Based Analysis
-
Precise Measurement: ASET gives you a precise, visual understanding of a diamond’s light performance. Unlike traditional cut grading, which focuses primarily on proportions, ASET focuses on the diamond’s actual light behavior.
-
Easy to Use: Whether you are a professional or a consumer, the ASET tool is relatively easy to use and can be a helpful guide when viewing diamonds in person.
-
Ideal for Any Diamond Shape: While ASET is most commonly used for round diamonds, it can be applied to any shape, making it versatile for all diamond cuts.
Conclusion
The ASET scope is an essential part of the diamond buying process, offering a detailed analysis of a diamond's ability to reflect light. By understanding how light is handled by the diamond, you can make a more informed decision when selecting a diamond that offers superior brilliance, fire, and scintillation.
If you’re looking for a diamond that performs well in all areas of light return, be sure to look for an ASET map that shows a balance of red, green, and blue areas with minimal light leakage. This will ensure that the diamond sparkles beautifully and delivers the stunning visual appeal you’re seeking.