How to draw sea glass

I thought it would be fun to try different materials and techniques to draw or paint sea glass. This could be useful, for example, if you wanted to record different pieces in your collection and where you found them. 

I started by drawing the outlines of some sea glass shapes. I then filled these in using different materials in four steps. The first row is coloured pencil, the second Tombow markers, and the third is watercolour. I used a similar technique for each of them.

1. I used one colour to roughly fill in each piece.

2. I used the same or a similar colour to go over this and give more depth.

3. I added more shadow using grey inside the sea glass pieces.

4. I added a shadow under each piece using grey.

And here's how I've used the Tombow markers version in my bullet journal.