how pearls are created?
351886
Pearls are created by certain molluscs most notably oysters as a result of irritation. As a response to an irritating object inside its shell, the mollusk will deposit layers of calcium carbonate (CaCO3) in the form of the minerals aragonite or calcite (both crystalline forms of calcium carbonate) held together by an organic horn-like compound called conchiolin. This combination of calcium carbonate and conchiolin is called nacre, or more commonly mother-of-pearl.
1185528
Calcium can be obatined from coral and oyster shell, as well as (I think) the calcium that comes from the earth.  Calcium contains animal derivatives in the sense that coral calcium  comes from coral which are the endoskeletons of coral; oyster shell calcium is derived from (big surprise) oyster shell and calcium generally is a skeletal product but can also be made by electrolyzing lime in mercury.  As to how the tablets are made, I believe the powdered calcium, along with such additives as carbonate, phosphorus or Vit. D, is put in molds, pressure is applied and, voila, tablets.
97352
african americans make art with staw, beads, rocks, ect.\nthey make bead art with beads the size of an edge of the tooth pick.first they draw a design of what they want to make. Next they get some material and place glue or sticky stuff on it. After that they place the beads on how they whant their design.\nthey make alot more things than that, but that is the only one that i know how to make.they also make dolls, hats, boats, toys, and alot more things!i hope that answered your question!
241612
Due to Vinegar's Acidic property pearl gets fluffy slowly and feels like a foam.\nOnly high caliber Nitric Acid can melt pearl easily.\nVinegar is made of light hydrochloric acid and tartric acid.
439747
Here's a piece of the answer:\n\nThe important thing to remember is that the snails MUST have a constant supply of calcium to keep the shell strong (the shell is, after all, the snail's home, and without it, he'd die!!).
687221
A sphere can be formed by rotating a semi-circle about a diameter. \nLet us consider the circle x^2 + y^2 = r^2. \nIt is a circle with centre at the origin (0,0) and radius 'r'.\nIf the semi-circle of this circle which is above the x-axis is rotated by 360 degree about the x-axis (which is also a diameter) then a sphere of radius 'r' is produced. \n\nThe volume 'V' of any solid produced by revolution of the portion of the curve y=f(x) between x=a and x=b is \nV = pi*I(y)^2*dx in limits x=a to x=b\n[where 'I' denotes the integral sign]\n \n\nIn this case y^2 = r^2 - x^2 and the curve rotated is semicircle above x-axis so a = -r and b = r\n\nSo volume of the sphere is\nV = pi*I(y)^2*dx \n= pi*I[r^2 - x^2]dx in limits x=-r to x=r\n= pi*I[r^2]dx - pi*I[x^2]dx in limits x=-r to x=r\n= pi*r^2*x - pi*x^3/3 in limits x=-r to x=r\n= [pi*r^2*r - pi*r^3/3] - [pi*r^2*(-r) - pi*(-r)^3/3]\n= 4*pi*r^3/3
675407
The Columbia Encyclopedia on Yahoo! notes\n\n"The processes of glassmaking have remained essentially the same since ancient times. The materials are fused at high temperatures in seasoned fireclay containers, boiled down, skimmed, and cooled several hundred degrees; then the molten glass (called metal) is ladled or poured into molds and pressed, or is blown (sometimes into molds), or is drawn. The shaped glass is annealed to relieve stresses caused by manipulation, then is slowly cooled. The glass, formerly annealed on shelves in a melting furnace, is now usually carried on rollers through annealing ovens (lehrs).\n\nAlthough today most hollow vessels such as light bulbs or containers are machine blown, fine ornamental hollow ware is still made by gathering a mass of glass at the end of a long, iron blowpipe, blowing it into a pear-shaped bulb, which is rolled on an oiled slab (marver), shaped with tools, and then reblown, often into a mold; the glass is reheated periodically in a small furnace (glory hole). It is finally transferred to an iron rod (punty) attached to the base of the vessel, and the lip is shaped and smoothed. Methods of decoration include cutting, copper-wheel engraving, etching with hydrofluoric acid, enameling, gilding, and painting."\n\nYou can gain more information here.\n\nhttp://en.wikipedia.org/wiki/Glass\n\nAs well as here \n\nhttp://www.cmog.org/
812248
I taught and explained the process to my children using four different colors of Lego blocks in two different heights.  I used shorter blocks to represent the C and G, and taller ones for the A and T.  If you glue them in the correct matching pairs to two pieces of ribbon, you can match up sides and part them again.  I undid the bottom half of the ribbon chain so they could see how free neucleotides were able to come in and attach.  You have to be abit careful since the Legos tend to come apart if handled too roughly, but at least they can visualize the differences and how the four types combine.   Since the legos were glued to the ribbon, I could also twist it to recreate the double helix.
92292
Gems - diamonds, rubies, emeralds, sapphires - just need to be cleaned and polished. They already exist in a usable form (after you cut and polish them.) You just need to wash the dirt away. \n\nOres are big piles of dirt that have bits of metal (iron, lead, silver, gold) in them. You have to refine the metal out and melt it into bigger pieces. It is a little like evaporating salt water to get salt.
688702
incomplete question, but the answer is pearl
489543
long colored beads or macaroni noodles, string (or wire), and beads... cand remember exactly what goes where but you get the idea
611568
4) How is Bounty made? \n\n \nWe make Bounty from trees that are processed into pulpwood. Long fibers from softwood trees, such as pine and spruce, are used. After debarking, the pulpwood is turned into chips that are cooked. The natural "glue" that holds the fibers together is removed, leaving a fibrous pulp mixture. The pulp goes through cleaners and screens and is bleached to make it absorbent. The pulp then goes through a high-speed paper machine. A translucent substance called resin is added to the mixture to strengthen the paper when it is wet. The water is removed and the fibers bond to form sheets of paper. Two layers of paper are combined with a thin layer of adhesive and embossed to form many tiny air pockets that rapidly attract moisture. Diamond shapes are pressed into the paper to give it a quilted pattern that holds water. Designs made with water-based printing inks are added to some Bounty rolls. For additional information about the papermaking process, visit http://www.wipapercouncil.org/.
982272
Actually oysters are not the only mollusks that can produce pearls. Any bivalve mollusc, such as clams, mussels, cockles, etc. can make a pearl. However most of these pearls are not vaulable. The mantle of the animal creates the pearl. It also creates the shell. Therefore the exterior of a pearl will have the same appearance as the interior of the shell. Pearl oysters (not the kind of oysters we eat) have a highly glossy, iridescent interior. Therefore pearls which they produce are likewise highly glossy and iridescent, which is what gives them their value. A pearl from an ordinary edible oyster would just be dull white, with no gloss at all, because that's what the interior of an edible oyster's shell looks like. Fresh water mussels produce semiprecious pearls because their shells do have a "pearly" interior, though not as "pearly" as that of a pearl oyster.
402812
You could try this link: \n\nhttp://www.vistapearls.com/about_us.asp\n\nIf you scroll down the home page, you'll see an offer of a pearl care booklet that comes in a silky Asian pouch to fit into your jewelry case.
457718
Hmm. I don't think seashells are formed from sands. Seashells are marine creatures to be exact, marine snails. Though I have yet been able to verify, I believe the reproduction process of seashells are similar to that of a snail. That is some seashells are hermaphrodites, producing both spermatozoa and ova, others are either male or female. They inseminate each other to internally fertilize the ova, thus producing fertilized eggs.
720118
"Females release thousands of transparent eggs in jelly-like strands into the water. \n Take a close look at a developing squid, or paralarva. It looks like a miniature adult. \n\nMales produce long tubes, or spermataphores, filled with millions of sperm. Most species have a modified arm for depositing these in or on the female. This spermataphore cluster is implanted on the head of a female (Abraliopsis sp.). No wonder scientists are puzzled as to how squid eggs get fertilized!"
381672
if you are trying to build a model - i would recommend either a playdo type creation or if you wanted to be fancy - use a jello mold.\n\nJello mold you make the mini components first and let them harden.  then put them in place in and outside of your 'membrane' and fill in with a clear jello (knox).  The clear represents your axon and cell membrane with your multicolored preformed pieces acting as your pump, na, and K+\n\nhave fun!