Les, Nick, Bryan....thanks for the comments.
Bryan....I took measures to get the crescents perfectly balanced. I stood them on their points on the table of my pillar drill, each point a precise distance out from the centre, then drilled them, so I'm happy that these are balanced, but you're right about the grain, it can make them look slightly off centre. I wanted these to have horizontally opposed tips (the upward facing crescent) as this is closely associated with some of the ancient Celtic knotwork symbols carved onto stones at religious sites. It has relevance to holding/storing riches of any type (grain, health etc etc).
I have since researched other depictions of the crescent and find that it occurs in just about every religion and culture on earth, with all manner of orientations, so I suspect I'll be making a lot more of these if this first batch sells.
Incidentally, this batch will be offered for sale individually rather than as a set.
Les