Guo Ying

10 Questions 5 Answers 0 Followers

Questions related from Guo Ying

Is there any other way to measure and quantify the color of a sample other than contact measurement and photography?

Gemstone is a kind of sample with special physical appearance. Are there any test methods or instruments recommended for the following situations? 1. Testing gemstone samples with high...

09 September 2019 8,421 3 View

How to exclude the influence of surface luster when evaluating gemstone color by human eyes?

The color matching method is very common in the process of gemstone color evaluation, using master stone or standard color card. When the luster of gemstone is obviously different from that of...

07 July 2019 9,245 2 View

Is there an algorithm that can convert Munsell color system to CIE colorimetric coordinates ?

The Munsell color system uses a three-dimensional space to represent three basic visual psychological attributes of various surface colors, amely Hue, Value and Chroma, and labels each color...

03 March 2019 5,695 3 View

How to identify a color-treated red jadeite? What is the principle of red enhancement when red jadeite is heated at high temperature?

The most of natural high-quality red jadeites are too small to be gemstones, so the heat treatment in the market is very common. Heat the deep-red one at a high temperature to turn it into a...

02 February 2019 3,522 2 View

When using X-rite Color i5 to measure the color of samples, which light source should I choose?

When using X-rite Color i5 to measure the color of samples, there will be several groups of data under different light sources shown on the instrument. Since the testing area is an enclosed...

01 January 2019 4,078 2 View

What is the difference between 2° and 10° illuminant observer?

Different experiments can be applied in different test conditions. How to choose the illuminant observer in the quantitative test of gemstone color? According to different purposes or the actual...

01 January 2019 3,426 2 View

When should we select Specular Component Included（SCI） mode?

When we use the spectrophotometer to measure the color of the samples ,there are two modes , one is Specular Component Included（SCI） , and another mode is Specular Component Excluded （SCE）， so...

01 January 2019 8,134 3 View

How to interpret color difference formula CIE DE2000?

CIE DE2000 (ΔE00) formula, which recommended by Commission Internationale de L'Eclairage (CIE). It's widely used around the world. How to understand it and use it properly?

12 December 2018 718 5 View

How to evaluate a gemstone whose color is obvious only under transmitted light?

There is a kind of jade similar to omphacite, with special attributes characterized by blackness in the reflecting light, greenness in the transmitted light . Now we need to establish a color...

12 December 2018 4,972 3 View

Is it feasible to evaluate the gemstones' color quality by the images taken with cameras?

When a gemstone is photographed with a camera, the body color of the gemstone changes. Different camera settings, photographs taken are also different. Is the color of iridescence, fire, changes...

12 December 2018 8,144 6 View