Your pic exemplifies well this particular type of Golden Wattle, not that we have other species of Golden Wattle but, the wood changes depending on where they grow, age/tree size, cut green, seasoned and or spalted woods. This blank is from the very old tree that I found dead near a creek, the tree was large and broke at the stump over the creek, being, for the most part, suspended but a couple of meters towards the base/stump the wood was in contact to the moist ground, therefore, producing some amazing spalting.
This blank was not from the spalted area but from somewhere in the middle of the tree, this was indeed the first Golden Wattle I found followed by many others that have shown me the colour variations particularly the reds and browns depending on what stage of the tree life I cut it or found it cut by others, knocked down from the wind.
Browns and yellows are predominant of the older wood while newer wood that was still alive when cut, reds are more vivid and the only way to keep these reds from darkening into browns is to process the wood green, season it (about 12 months) keep it out of sunlight and then coat it with something, the reds will never fade that way.
Thank you for showing your work and particularly a pen dressed with one of my "stable" woods.