Any student up to twelfth grade can submit a crystal in the "Alum" competition. (Teachers can also submit alum crystals for a special "teachers only" competition)
 

The maximum starting material is limited to 100 g for any given crystal.
 

The number of submissions is limited to 3 per classroom or household (two for overall/quality and one for coolest crystal). It is recognized that where several crystals from a school or household may be of roughly equivalent overall quality, and it is difficult to make a choice, it may be necessary to submit several crystals. If more than two crystals are submitted by a classroom/household for the overall/quality category, we reserve the right to preselect two crystals for judging.
 

Each submission will receive a Quality and Overall score.
 

Prize winners in the Overall category will be determined based upon their overall score. All remaining crystals will be re-ranked and judged according to their quality score.
 

Each classroom/household is limited one prize winning crystal per category.
 

The minimum size for any submission is 0.5 g.