This set of images should give you a decent idea of the concept which I have mentioned a number of times here. Most recently, you saw me use a technique like this on the Reapercon glazing figure.
There are three glazing colors on the palette. They just happen to be a red, a blue, and a yellow.
However, each one has very different chemical properties. As they interact with each other, things get very interesting!
The blueish color is placed first... it's Secret Weapon Storm cloud. In some places, it is mixed with Vallejo Fleshtone shade. That would be the pink color on the armor plates.
When a dot of the Vallejo sepia wash is placed in the still wet color, it reacts to those other colors, being mostly 'repelled', which prevents it from mixing completely with those previous washes.
It creates a sort of corrosion or barnacle effect, just perfect for a mostly under water creature!!
I worked my way around the armor plates, careful not to do too many at once. As with any watercolor style technique, timing is everything. This view shows the difference between the plates that have been glazed and the original form.
The palette reveals a bit of this chemical reaction. If you look at the blue color, see how there are all sorts of interesting ripples and cracks in the wet paint.
The idea is to put down just enough of the blue and red paint to 'suspend' the dots of sepia wash. This will be enhanced later with other semi-opaque layers of color.
Once those initial layers dried, I was able to add a few more dark spots... dabbing at the edges with a damp brush to feather them out.
Here are the colors in person!
The view from above displays the unusual patterns than are created. Just like with watercolors, you never quite know what's going to happen.
I was also trying to play these warmer colors against the more saturated teals and blues of the scales.
Here's a much closer view of the "sedimentation effect", as it is known in the watercolor world. The various glazes from companies such as Secret Weapon and Vallejo interact with each other in very interesting ways like this.
Obviously, this takes a lot of experimentation to figure out. However, it's definitely worth it in the end!!
I hope this made some sense to you all. :-)