 The instructions encouraged laboratory cleanliness by cautioning users not to break the seals on three of the ore sample jars, for "they tend to flake and crumble and you would run the risk of having radioactive ore spread out in your laboratory.This will raise the level of the background count", thus impairing the results of experiments by distorting the performance of the Geiger counter.The set originally sold for $49.50 () and contained the following