HOME-MADE CRYSTALS

Radio Record, Volume I, Issue 27, 20 January 1928, Page 15

HOME-MADE CRYSTALS

A SIMPLE RECIPE, Supet-sensitive crystals at 2s, 6d. per gtoss! Here’s how. Get some pure lead (Pb.), not solder or lead alloy Also some flower of sulphur--ordinary powdered sulphur. -Cut the lead in small pieces and mix with the sulphur in the ratio of seven parts by weight of lead to one part of sulphur. Place the mixture in a crucible, a tin cup, or some convenient container other than glass or porcelain. Heat over a Bunsen burner or over réd coals in a stove. In a vety short time the mix: ture will begin to glow and the lead and sulphur -will fuse together. At this point, remove the mixture from the heat and place the container in a basin of cold water to cool. Water to be Avoided, Do not let any water get on the crystal, as it will ruin them If you have had thiugs just right. you will have a lump of material that is suyersensitive over its entire surface. ~ If the lump is crumbly, you have "‘cook- . ed’? it too long, and if it is streaked with lead vou did not cook it long enough, or else you used too much lead = Your ervstal will then be sensitive onlv in spots, and not over the entire surface as it should. Use a verv light contact. Some home-made ervstals are as good or better than the best natural crvstal ever used Tine for reflex, too! The above materials may be purchased at any chemists.