The Malachite Green solution (HT8028-250ml and HT80616-500ml) has not been tested for use in various procedures to stain spores. There is a Schaefer and Fulton Modification of the Wirtz Spore stain, which lists the formulation for the Malachite Green solution as simply 5% malachite green solution in water. However, the HT80 procedure lists a different formulation for the Malachite Green solution intended for use in staining Acid Fast Bacillus (AFB), which contains malachite green oxalate, acetic acid, and glycerol in deionized water. Given the difference in formulations and the inclusion of an acid differentiator in the HT802 formulations, no claims can be made that this solution is suitable for staining spores. The solution might work, or it might not.
A better option might be to order kit 04551-1kt-F, the Schaeffer and Fulton Spore Stain kit, which consists of a 5% solution of Malachite Green as the first component, and a Safranin O solution 0.5% as the second component.