What is this stone

I found this stone and it seems strange to me, does anyone know what it is

 

Where are you? Where did you find it?

 

in a field near Kings Lynn, UK

 

Cool! Sort of looks like yellow jasper something. Probably called flint in the UK

 

How about this?

http://www.stoneagetools.co.uk/what-is-flint.htm

Internal flint cast of a sea urchin.

Flint nodules in the chalk changed over time as their outside acquired a whitish-coloured cortex or rind, possibly through ground water percolating through the chalk.It’s thought the cortex formed because the flint surface is slightly more soluble in some microscopically small areas than in adjacent areas, so there is differential dissolving at the surface which results in a microscopic sponge-like structure. The cortex can be 5mm or more in thickness. When people started making tools from flint, they often removed the external cortex to get at the fresh flint inside, although in some cases they left a smallamount of cortex to make some tools, such as scrapers and knives, easier to handle

 

Yes, it looks like that.
Thank you!

 

Beat me to it. The patterns and holes are the remnants of an ancient lugworm's poop. Or several lugworms. Kings Lynn was once sea. They tunnel ferociously in sand: I've dug for them.

This is what they poop:

 

An old matzo ball. Just kidding.

 

Ah, yes, the old lugworm latrine, very desirable.

 

It looks "shale" based, perhaps mixed with coral? Just my WAG..

 

I think Joe Dirt once found something like that?

 

If it's East Anglia fossil, limestone as a base probably.