If you have a small mineral sample, why might testing for cleavage be one of the last things you do?

If you place one drop of cold hydrochloric acid on calcite the entire drop of acid will erupt with bubbles and a vigorous fizz will last for a few seconds ... For example, magnesite has a very weak reaction with cold HCl ... These rocks might contain small veins or crystals of carbonate minerals that produce a fizz in contact