Question:
> Gallstone Colors? What do the colors indicate??


Answer:

Bile, or gall, is composed of water, bile acids and their salts, bile
pigments, cholesterol, fatty acids, and inorganic salts. Bile acids are
synthesized in the liver from cholesterol.



Pigments are organic coloring molecules within the body. They may be found
in the bile, blood, urine, choroid (eye), or skin and hair. Blood, bile and
urinary pigments are derived from hemoglobin or the products of hemoglobin
catabolism.



Common Bile Pigments:


Bilirubin (linear tetrapyrrole)
color: yellow or red.
Source: liver



Biliverdin (linear tetrapyrrole)
color: green or blue
Source: oxidation of bilirubin


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Bilirubin is modified in the liver to increase its solubility in aqueous
media and the product is secreted into the bile. Microbial conversion of
the bile pigments in the large intestine finally yields products that are
responsible for the yellow color of urine (after reabsorption of the
pigment from the large intestine) and the color of the feces.


Those pigments are responsible for progressive changes in color of a
hematoma, or bruise in which the damaged tissue changes its color from an
initial dark blue to a red-yellow and finally to a yellow color before all
the pigment is transported out of the affected tissue.
========




Most likely, green (shiny, almost transparent) stones are coming out from
your liver. They can be also blue-green.


That is just pure cholesterol and Biliverdin.


Bile is alkaline fluid of a green-blue, yellow or brown color.



So, Bile can be green (biliverdin). Bile can also be more yellow/red/brown
(bilirubin).


Bile pigments are the products of the breakdown of hemoglobin removed by
the liver from old red blood cells. The yellow and brownish/red color of
the bile pigments imparts the characteristic yellow/brown color of the
feces. Color is due to bacterial action on bile pigments.


In normal individuals, intestinal bilirubin is acted on by bacteria to
produce the final porphyrin products, urobilinogens and urobilins, that are
found in the feces. Bilirubin and its catabolic products are collectively
known as the bile pigments.


Feces are normally brown or dark brown in color, soft, and formed. Bile
pigments give feces their characteristic color. The typical odor is caused
by nitrogen compounds that are produced by the action of bacteria.




So, Yellow and red color comes from bilirubin.


Most likely, yellow stones are coming out from your gallbladder.



They are often yellow outside, but green inside. (possibly indicating that
stones started forming inside liver)



Yellow color may (I say may) be also produced through digestion.
Possibly as a chemical reaction between stone, bile, digestive juices and
bacteria.



Black & brown color comes from Black and brown bile pigments.



There are few web sites and photos of liver (photos taken after autopsy). On those photos, liver contains green stones.



Yellow is the most common color of stones inside gallbladder.