The method was developed to detect crystals (calcium oxalate) in plant and animal tissues and stain the bacteria by using silver nitrate solution2%. By adding the prepared solution to the bacterial fixed on the slide and leaving it for 10 minutes at room temperature, then expose the slide to ultraviolet light for 30 minutes. Also expose the slide of animal and plant tissue to ultraviolet light for 30 minutes. The color of the animal and plant tissues shown to be pink to light brown due to the reduction of silver metal and the penetration the silver into the cell and tissue. On the other hand, the bacteria especially those produce spores and capsule are appear brightly under the optical microscope, distinguishing the bacterial cell. The results showed that the crystals in the plant tissue and increased susceptibility of tissue to take the stain, in addition to the possibility the kidney stones in animal tissue to take the silver stain and seen critically.