Topic: A - Z challenge 5
I've always thought of onyx as being a black stone but, when I researched it online, I found that it comes in many colors more commonly than black and they often are banded or resemble marble.
I followed the look of one illustration I found and duplicated the stone using alcohol inks and blending solution on a non-stick mat, smooshing glossy cardstock onto it and drying with a heat tool.
This piece of the finished background looked like water so I added stickers and mounted it to create this underwater scene.