This distinction does not come from our mining practices, but rather from our bodies abilities to produce kidney stones.
Kidney stones are the most common urological problem in the United States.
Kidney stones develop from minerals dissolved in the urine. Usually the urine contains chemicals that prevent this crystallization but, occasionally these minerals precipitate out and form crystals on the inner surface of the kidney. When stones form in the renal pelvis they are called kidney stones, and when they form in the bladder they are called urinary stones. Struvite stones are usually found in association with bladder infections and are also common in Dalmations. All tests require a piece of stone that is approximately the size of a match head.