What kind of bead is this?

Dark...

Seriously you need a more focused picture with better lighting and detail of the hole and interior at least for these old eyes.

 

i was gonna say ...round.... sniped by Reader !!

 

I'd say wood that has seen some hard times. What does it feel like? Is it light, or heavy?

 

Yemeni black coral maybe?


Mine are more black than these, but not as rough looking as yours.

 

You know what... For @johnnycb09 entertainment, I'm going to say... for testing...Taste it!

 

I have not seen Yemeni black coral before. Neat!
But I would not expect coral to be a fibrous as Kingjoker's appears to be in the damaged areas and in the center hole.
It looks like a worn version of these olive wood beads:

https://www.thebeadchest.com/produc...MIm5_CrZro3gIVgiSGCh22WQUREAkYDCABEgIXFvD_BwE

 

Are you being, uhm, kyra again, kyra?

 

It is very difficult to discern, and connect it to something familiar, isn't it?
It is fibrous and could be wood. But then again, Yemeni and other Asian black coral is fibrous as well.

 

I improved the pics...
It seems having carved or molded decor

 

It almost looks like lava.

 

It is hard to tell from the photos if the "carved" concentric rings occur only on one side of the bead or if they are on other sides as well. This might help in determining if it is natural or a man made effect.