Letter - O

I have really enjoyed the crescents! There was a bit more thinking outside the box than I managed for mine.

And here is a challenge! The prompt for the rest of March is the Letter O. It just might be a bit hard! It just might take a bit of lateral thinking! or maybe something springs to mind straight away?

You can post photos of something you have made or something you are thinking of making. You can post something intriguing you have seen or something that stretches the mind to how it fits. (but do tell us!)

Please use the label O when you publish your post.

So here I am thinking laterally.
O is for Oxidation.
Some rust dyed fabric I did...

...which eventually became this!