These are the horn spines for my vellum exemplars. They are just short of A6 height. All are the same size, I took the photo at an angle so the grain of the horn would show up. They will have holes drilled in them and attached as spine support.
And boy, was it hot yesterday. Two straight days of 40C. I was checking the weather for tomorrw at 7pm, it was still 37C!! And we haven't got to the hot part of the year yet. Lucky I like this weather.