If you think that all canaries are yellow, you join the company of hundreds of folks who have this common misconception.  The wild canary, when first found and captured on the Canary Islands was not a yellow bird.  It appeared to be green, but was actually a bird of yellow ground color with a overlay of black/brown melanin pigment.  This transparent overlay alters the ground color and gives the bird a green cast. 

The yellow canary is a mutation that occurred as people began breeding canaries in captivity a few hundred years ago.  Canaries were hatched without the melanin pigment, and as the yellow canary became more popular, birds with this color mutation were bred selectively to produce more birds of pure yellow.  This coloration became so common that the words "canary yellow" are now as recognizable as a description for a certain color as the words "lime green" or "sky blue".

In the illustration below, you can see how a black/brown overlay on a yellow ground color produces an olive green color.  Artists frequently combine yellow paint and black paint to get various shades of green.  I guess it shouldn't surprise us that God chose the same color combination to get the original green of the wild canary.

American Singer canaries are also found with white ground color.   This photo is of a dominant white canary hen.  The gene for white is dominating the yellow ground color so that it only appears on the edges of the flight feathers (wings). 

When the melanin is black/brown, the white ground colored bird is said to be a "blue" canary.  This "blue" is not like you would see on a parakeet, but is actually appears to be more of a slate gray.  This photo shows a blue hen.

You will also encounter canaries where the black pigment is absent from the melanin.  The brown melanin that is left changes the appearance of a yellow ground colored canary to a warm cinnamon color.  This coloration is know as the "cinnamon factor". 

When the brown melanin gene occurs in a white ground canary it produces what is termed a "fawn" color, which is more of a beige appearance. 

The cinnamon inheritance is carried genetically, and is a sex-linked gene that can be passed on from either the father or the mother.   For those of you interested in breeding canaries, you should refer to a Color Pairing w/Cinnamon Factor Chart.PDF that shows you the possible results in offspring, color-wise, when you pair a male of a certain color with a hen of a certain color.

	You will notice that these two-day old nestmates have different colored eyes.  The one on the left has garnet colored eyes, while the baby on the right has black eyes.  Garnet colored eyes are an indicator that the chick on the left is a cinnamon.  As the chick gets older, they eyes will darken and will appear the same as non-cinnamon birds. It is possible to determine the sex of a chick this young in some cinnamon pairings.  The baby on the left in this photo is a girl.  The chart referred to above gives you clues as to what sex garnet eyed chicks may be depending on the parent's cinnamon traits.
A garnet eyed baby on the left with her normal sibling
Here are the same two babies at about three weeks old.  The cinnamon baby has feathered out with the white ground color of her mother, so is technically called a "fawn".  Her garnet colored eyes have darkened and look the same as her nestmate now.  At this age, their instinct has them crouch down and remain still when a "predator" (including a human) is around.
	The fawn hen and her sibling nearing 3 weeks of age
Here we see the fawn hen in the weaning cage and not looking so much like a baby anymore.  It is amazing to see them develop and change from helpless chicks to independent beings in only a few short weeks. Seeing beautiful color patterns like these make me glad that canaries are not just a YELLOW bird!!!
	The fawn hen and her sibling nearing five weeks of age.

Melanin can be totally absent from the bird, which is what you see when you look at a canary that is completely yellow, or completely white.  This is called a "clear" bird.  All you are seeing is the pure ground color of the bird.  When melanin only affects a few feathers in a patch no bigger than a dime, the bird is called "ticked". 

To the other extreme, a bird totally covered with the melanin overlay is called "self".  When one of these dark birds has only a few feathers showing of the ground color, it is referred to as a "foul" bird.

Everything in between the ticked canary and the foul canary is called variegated.  This is where the pattern or patches of melanin appear anywhere on the bird.  Each variegated bird is different, and the coloration can be quite beautiful. 

Most of the singers you see on the show circuit with the most varied songs are the medium variegated to self in coloration.  Some believe that as the coloration lightens, the variety of song decreases.  I'm not sure that is true, as I've recently seen some clear yellow birds in the winner's lineup at bird shows.

This is a beautifully variegated hen with yellow ground color.

The white "frosting" on her feathers is due to her "soft" feather type.

Feather type also affects the color of the bird.  There are two basic feather types in canaries..... hard and soft.  In the hard feather type, the color in the feathers is intensive and covers the entire feather.  In the soft feather type, the ground color is less intensive and does not extent all the way to the outermost tips of the feather, but stops short, leaving the tips white.  This makes the bird look frosted.   A soft feathered bird also differs slightly in structure, in that the soft feather is somewhat larger, broader and softer in texture.

Breeders of different types of canaries use different terms to describe feather type, and the terms are one of the things that often confuse newcomers.  This chart should help.  The terms on the left side of the chart all mean the same feather type on one end of the spectrum.  Similarly, all of the words on the right side of the chart are referring to the opposite feather type.