Collagen contains specific amino acids â Glycine, Proline, Hydroxyproline and Arginine. These amino acids have a regular arrangement in each of the three chains of these collagen subunits. The sequence often follows the pattern Gly-Pro-X or Gly-X-Hyp, where X may be any of various other amino acid residues.ollagen contains specific amino acids â Glycine, Proline, Hydroxyproline and Arginine. These amino acids have a regular arrangement in each of the three chains of these collagen subunits. The sequence often follows the pattern Gly-Pro-X or Gly-X-Hyp, where X may be any of various other amino acid residues.
Opal is one of the world's most beautiful and precious gemstones, predominantly found in Australia. It is one of only six types of precious gemstones found on planet earth, sharing prestigious company with diamonds, rubies, sapphires, emeralds, and pearls.
When common opal is found in association with precious opal, it is known as potch. About 95% of all opal mined from the opal fields is common or potch, that is opal that is basically one coloured, i.e. white, grey, black, and is only suitable for backings for doublets or triplets.ver 95% of the world's precious opal comes from Australia, and opal is Australia's national gemstone. While several different types of opal are present in nature, there are two main varieties-precious opal and common opal or potch. Precious opals exhibit the characteristic play-of-colour, and is comparatively rare.