The chemical formula of the mineral Bayldonite is indicated by Cu3Pb(AsO4)2-H2O or Hydrated Copper Lead Arsenate Hydroxide. Bayldonite is actually a Phosphate mineral. Mineral Bayldonite was first discovered by John Bayldon in a mining area found at Cornwall, England. In the year 1865, Bayldonite was first classified as a mineral. The Bayldonite chemical formula however was only discovered in the year 1956. Bayldonite was named after John Bayldon, a British physician. Bayldonite is known to crystallize in the monoclinic system of crystal formation. In optical mineralogy, the monoclinic system of crystal formation comprises crystals having three axes of unequal lengths. Two of which are usually found in a position that is oblique or not perpendicular to one another. However, both of which are commonly found perpendicular to the third axis. Bayldonite is also considered as another attractive arsenate mineral that commonly exhibits wonderful microscope images when viewed with the aid of the petrographic polarizing microscope used in optical mineralogy. Mineral Bayldonite is commonly found exhibiting a nice green color with high resinous luster when it is viewed in reflected light of polarizing microscope.
Bayldonite mineral specimens are usually found in shades of green to yellow green or yellow in both transmitted and reflected light of polarizing microscopes for mineralogists or the ones used in the field of optical mineralogy. Specimens of mineral Bayldonite is most commonly found exhibiting a resinous luster when viewed in reflected light of petrographic polarizing microscopes for geologists. The green color of Bayldonite mineral is brought about by its hight copper content, which can be found in its chemical composition. Its high luster on the other hand is due to its high lead content. Some Bayldonite specimens are found containing some amount of zinc in its chemical composition. Bayldonite is commonly found having absent cleavage even if it is evaluated under several adjustments of the aperture diaphragm of the petrographic polarizing light microscopes. Bayldonite usually exhibits uneven fracture when viewed under polarized microscopes used by mineralogists. Uneven flat surfaces that are commonly fractured in an uneven pattern are most commonly clearly exhibited by Bayldonite when it is viewed under polarizing microscopes used in optical mineralogy. In optical mineralogy, fracture describes how a mineral breaks when broken contrary to its natural cleavage planes and this can be seen when the crystal examination is made under several stage rotation or aperture diaphragm adjustments on polarized microscopes. The specific gravity measure for mineral specimen Bayldonite commonly gives an approximate value of 5.5 grams per cubic centimeters, which is usually considered well above average value for translucent minerals. The hardness measure for mineral Bayldonite when it is evaluated using the Mohs scale method is usually 4.5. When mineral specimens of Bayldonite are rubbed on a white porcelain streak plate, they usually leave a green streak. There are some specimens found with dark green crystals of Bayldonite lining the cavities of a white quartz matrix.
Bayldonite mineral crystals are commonly found in transparent to translucent in appearance. Crystal habits of Bayldonite commonly include tabular crystals, which are usually found shaped like a book when viewed with the aid of polarizing light microscopes used in optical mineralogy. Bayldonite crystals can be also found in radiating fibrous crystals, sometimes in granular and massive crusts, all of which can be seen more clearly exhibited when the mineral is viewed under petrographic polarizing microscope. In optical mineralogy, fibrous crystals, as described, show individual grains that are long slender fibers, which commonly shows interesting microscope images under petrographic polarizing light microscope. Radiating crystals on the other hand is described in optical mineralogy field as elongate grains that radiate out from a center, and this is usually a splendid view under polarizing light microscope. Bayldonite minerals can be also found as botryoidal crystal clusters, which are clearly identified with the aid of polarized light microscopes.
Some Bayldonite mineral specimens are found powdery to fine granular in form. They can be also found as minute mammillary concretions. Mammilliary formation is a larger breast like rounded forms that resembles botryoidal. Sometimes, Bayldonite minerals are found in druse form, which commonly show crystal growth in a cavity that results in numerous crystal tipped surfaces that are splendidly exhibited in transmitted light of petrographic polarizing microscopes. They can be also found as encrustations, which usually forms crust like aggregates on matrix. When viewed between crossed nicols of petrographic polarizing light microscopes, Bayldonite mineral specimens are commonly found displaying a biaxial positive figure. It is also commonly found showing a very high surface relief that can be seen more clearly visible when the mineral is evaluated under several adjustments on the aperture diaphragm of polarizing microscopes used in optical mineralogy. It shows relatively weak dispersion in plane light of petrographic polarizing light microscope. There is no specific data on toxicity and health dangers for mineral Bayldonite. However, Bayldonite specimens should be treated with great care and use of sensible precautions are advised upon handling them. Bayldonite minerals are found not radioactive after several chemical tests made.
Bayldonite minerals are commonly associated with other interesting minerals such as limonite, duftite, quartz, mimetite, cerussite, bindheimite, azurite and wulfenite. The best field indicators of mineral Bayldonite commonly include color, streak, density, crystal habit, locality, lack of cleavage and its splendid association with other interesting minerals. Bayldonite minerals are considered as secondary minerals, which are formed in the oxidation zones of copper ore-bearing veins. Bayldonite minerals are commonly formed in the oxidation zone of ore deposits. Nice Bayldonite mineral specimens are found at Penberthy Croft Mine, St. Hilary in Cornwall, England. Bayldonite mineral specimens can be only found in a few localities. They are considerably scarce minerals and any specimen is undeniably treasured when found. Bayldonite minerals can be also found in localities like the Wheal Carpenter Mine, St. Day, Cornwall, England; Tsumeb, Namibia and Arizona in the United States.
