Does anyone recognize this mark?

Hi I was wondering if anyone recognized this mark at first I thought it was wood with the sun burst, but totally different from Rookwood marks and the more I look at it, it looks more like a Shell. Hopefully someone knows what it is

 

Try rubbing a little cinnamon or baking soda in the mark to see what stands out in the middle and bottom.

Could it be a thistle in the middle?

 

My first thought is a pair of crossed antlers and a sunburst perhaps.

 

Apologies on the late response I work nights, I put some cinnamon on the marking, by the way that was a great idea never tried that before. Here’s the new photo.