Beryllium is a good metal to use as an example. It is quite the rare element in the crust. Estimates of between 2 and 6 parts per million exist on our planet (compare to Silicon, which is rather abundant at 270,000 parts per million in the crust). Not only is the metal quite important to the military and medical industries because of its inherent properties (it is very lightweight, invisible to X-rays, and terrifically strong), it also has use in its mineral state as an adornment. Many people wear Beryllium ore without even knowing it. Do you have an Aquamarine or Emerald in a piece of jewelry? These gemstones are the most pure form of the primary ore of Beryllium, the mineral group aptly named ‘Beryl’. Both Aquamarine and Emerald are both gem grade varieties of Beryl, as are the gems Morganite, Bixbite, Goshenite, and Heliodor. All share the same basic chemical composition,
but due to different elements included in the crystalline lattice, they reflect different wavelengths of light. Chromium gives Beryl a rich green color, we call those ‘Emeralds’, pure colorless Beryl is called Goshenite, red is Bixbite, yellow is Heliodor, and pink is Morganite. “Common Beryl" is the mineral used as Beryllium ore, and it occurs as greyish to greenish opaque crystals and masses. It has no use in the jewelry industry, but the metal can be alloyed with Aluminum or Copper which makes the resulting alloy several times stronger than the base metal alone.