African Praying stool

I was told this is an African praying stool possibly from the "Ashante" tribe in ghana...I am looking for any information and if the information I have is correct.  I would love any information on possible value as i have seen these on line from a couple hundred to a few thousand dollars.  The age if there is any way to tell and how you tell ???.....Any information about the stool would be greatly appreciated.  I was told it was careved out of 1 piece of wood and it does look that way.  the measurement are as follows ...20 inches long about 9.5 wide and 12.5 tall.  Was told the wood maybe Mahogany but not 100 percent on that.  Thanks again