Then I hit on the idea of sorting them into little jars. I was given a few 'Purity' jars, which are just the right size.
After removing the labels and washing them, I spent a couple of hours this morning sorting them, and this is the result:
The tall jar on the left holds a mix of larger buttons; the next two small ones are yellow and brown on top, and pink and red underneath. Then a tall jar of small white buttons. Then we have a small jar od large white buttons standing on a jar of black buttons. Lastly, a small jar of blue buttons. All remaining buttons, such as green (not many of these), grey ones and metallics are kept in the biscuit tin. I hope that the time spent will save me time in the long run!