Creatinine is a normal waste product produced by muscle metabolism. When your kidneys are functioning normally, they filter creatinine and other waste products out of your blood and send them out of the body through urine. A creatinine urine test measures the amount of creatinine in your urine and can help your doctor evaluate how well your kidneys filter waste. This is useful in diagnosing or ruling out kidney diseases and some other conditions.
These terms are based on old traditions from the west. These days, all gemstones are considered precious since they are all rare and there is a limited supply of them. The traditional list of gemstones that are considered precious stones are: Diamond.
Are all gems minerals? A mineral is an inorganic, naturally occurring substance with distinct chemistry and crystalline structure. Gemstones are materials that have an economic or aesthetic value. Therefore, not all gemstones are minerals. For example, amber is solidified tree resin, so it is not a mineral. Gemstones can be classified as either amorphous or crystalline. Amorphous gemstones have no orderly internal atomic structure and no naturally occurring shape. Glass, amber, and opal are examples. Crystalline gemstones are minerals; they have a definite and regular internal atomic structure. Examples include garnet, emerald, and ruby. PROCEDURE: Most students are familiar with their birth month's gemstone. Poll your students and see if you can list the months and the gems just from their answers.