The dark factor is a mutated gene that changes the feather structure of a Budgie, deepening thus its color.
Any Budgie can inherit none, one or two dark factors from its parents.
The light green Budgie is the wild type Budgie and he has no dark factors.
A green Budgie with one dark factor (from either of his parents) is called dark green (as opposed to light green) and is a darker shade of green than the light.
A green Budgie with two dark factors (one from each of his parents) is olive green in color and is called olive green.

The same applies to the blue series:
The light blue Budgie is the wild type Budgie and he has no dark factors and is called sky blue.
A blue Budgie with one dark factor (from either of his parents) is called cobalt and is a darker shade of blue than the light.
A blue Budgie with two dark factors (one from each of his parents) is grayish blue in color and is called Mauve.



- A budgie with no dark factors, will not pass on the dark factor gene to his offspring since he has none.
- A budgie with one dark factor will pass it to 50% of his babies.
- A budgie with 2 dark factors will pass one to each of his babies.


Two Light Green

A dark green from the net



A sky Blue bird


A coblat


A mauve (he's whitewing too)

Regards

Thank you Pass for this valuable topic.

Great job.

Thank You Pass
I like A mauve
very nice

take care