Camphor is a naturally occurring substance which is usually obtained from the camphor laurel (Cinnamomum camphora). It is waxy to the touch and translucent white with a crystalline structure.
For its white coloring, and its cooling scent and effect of the skin, camphor has often been associated with the moon and is commonly found recommended in incense formulas of a lunar nature.
In many folk traditions camphor is seen as a cleansing agent and attributed with spiritual cleansing and protection. In some cases the camphor square is floated in a bowl of water and then set alight. this method however can produce harsh smoke from the camphor which has a scent similar to burning plastic.
Much more commonly camphor is placed in the four corners of a room, or the four corners of a house. This is usually accomplished by placing a square in a mojo bag and hanging one in the upper corners of each room that you wish to be spiritually cleansed and protected from malevolent influences. Anther option is to simply place the square on the ground in the corners of the room, though this should be avoided if you have animals or small children in the home as camphor can be toxic if eaten. In both cases a dime is usually included with the camphor, either on top of the square if placed upon the floor, or added to the mojo bag if hung up. Most appropriately this would be a mercury dime if you are able to fine one, as mercury dimes are often used for protection in hoodoo and rootwork. However, in a pinch either regular dimes, or an Indian head penny would suffice as a substitute. The camphor squares should be replaced with new ones each month.
Yet another way of using camphor, and one of my personal favorites, is to crumble a square in a small cup or bowl, cover it with a good deal of florida water, and place these either in the four corners of the house, or near all entrances and exits to the home. this serves to cleanse and purify the home as the florida water slowly evaporates. This method is best repeated every week to maintain the effect.