Another brilliant-looking pen! Well done that man!!!
Is it Australian Eucalyptus burl, Paul?
Bob.
Very clean pen indeed Paul , with a good finish on it too .. At a guess i would go with Eucalyptus as the wood, only because of the Green that you see in the wood ...
It could be eucalyptus, there are over 3,000 species, so if you're a betting man this will hedge your bets!
Other than that haven't a clue, could be many, but would place a fair wedge against maple, hard or soft, curly or not.