Just steep dried alkanet root inraw linsed oil for three or four months in a warm place. Use the resultant red oil on the bare, unfinished stock until the contrast an colour is enhancesd sufficiently. It is very difficult to over-do it.
The background wood should be a red-brown and the figure will be much darker (black) streaks. End result is also dependent on the wood - natural colour and figure, hardness, variation in grain etc.
I do not darken the oil finish mixture, as is the norm in the UK gun trade, I try to get the colour I want right and then add the finishing oil (which has no alkanet root in it), which brings out the lustre and depth in the figure.
If I do want the finish to darken, I use turpentine as a drier with the linseed oil and I first soak this turpentine in alkanet root for three months. However, I almost never use this recipe anymore.
To my mind the wrong colour really makes the difference between a good job and a bad job.
