Think of it this way—all coffeemakers are made of plastic, steel, and glass, the differences are how these materials are designed and implemented.  Higher quality coffeemakers make a better tasting cup of coffee.  Higher quality manufactured diamonds are in line with mined diamonds.
QUALITY VARIANCES:  It seems like grade variations are made out to be a more complex lab-created diamond issue then it really is.  Once boiled down, there are three primary grades of simulated diamonds—high, medium, and low.  For the jewelry shopper it should be noted that the quality of setting goes hand-in-hand with the quality of the gemstone.  Those that sell manufactured diamond jewelry off point-of-purchase displays in the costume jewelry sections of discount stores use low quality or scrap stones that are not gem quality, and have disco ball or murky look.

Those that sell manufactured diamond jewelry on the TV shopping channels—which is generally with a sterling silver or a micro-thin layer of gold plated over silver (Vermeil [pronounced ver-may]) settings—use medium quality stones not of gem quality.  Those that sell solid 14K gold or solid platinum settings, as a rule, use the highest gem-quality man made gemstones that replicate mined diamonds.
PRICING:  Low grade stones are sold in bulk to costume jewelry makers and are often glued on electroplated settings.  This jewelry is fine for children, where loss risk is high, and usually retails for less than $15 per item.  You will find medium grade stones primarily in sterling silver jewelry that sells for under $100 per item, settings and stones.  Medium grade simulated diamonds can be distinguished by the naked eye as not being mined diamonds.  High grade gemstone quality lab-created diamonds, undistinguishable by the naked eye from mined diamonds, are found mounted on settings of solid 14K gold and platinum.  This is considered to be fine jewelry, with the best quality gemstones selling for under $100 per carat for the gemstones alone.  Manufactured diamonds that sell for over $100 a carat are not higher quality than those that sell for between $80 and $100 per carat.

RECOMMENDATIONS:  If you are buying for someone that is likely to lose the jewelry, there is no reason to spend any more than you have to, and Wal-Mart will do just fine.  On the clearance rack you can even pick up some jewelry for less than $5 per item.  If you buy simulated diamonds set in sterling silver, expect decent stones, but they will fool few into thinking they are mined diamonds.  Also, your fingers are likely to turn green or black in response to a chemical reaction, not with the silver per se, but with the nickel/copper alloys in sterling silver.  With any plated settings, gemstones are low to medium grade, and the plating will eventually chip off, particularly around the edges.  When that happens, the nickel/copper alloys will be exposed, the setting will look like it came out of a gum ball machine, and your finger will generally turn green or black.  It is just a matter of common sense, if you want simulated diamonds with mined-diamond qualities, they must be set in 14K solid gold.  Jewelers who offer lab-created diamonds are not going spend on money on gold and not mount the highest quality stones, which would defeat the purpose of creating fine diamond-like jewelry and alienate customers.

The beads that we tend to think of as traditional beadwork are called seed beads ‚ because of their small size they resemble seeds. These beads were used in early beadwork ‚ the work of the Egyptians.

The Egyptians used a type of bead called faience beads. Our seed beads today are made of glass, but Egyptians were using beads long before the invention of glass. Their faience beads were made from quartz particles fused together. A glaze was applied over the quartz. The beads were then woven or strung into a variety of jewelry and clothing.

Beaded necklaces were found in the tomb of King Tut. Other beaded items in his tomb were a pair of slippers he perhaps wore as a child and a hassock. It’s unusual for ancient beadwork to survive since it was strung on cords made from leather and cloth, which tend to disintegrate with age. We are fortunate to have these few examples to give us a perspective on the history of Egyptian beading.

Some religious texts from India refer to beads being woven into hair and into horse’s tails. These references were recorded around the 9th century BC. And beads were also widely used throughout Asia in ancient times. There were beaded items found in temples in Japan that date back to 800 A.D.
Early beads were fashioned from shells, ivory and stone. Early Egyptians valued the beads according to the stone that was used to create the beads. Different stones were thought to have different properties.

Lapis Lazuli, a beautiful blue stone, was believed to protect the wearer’s health. This stone was often fashioned into beads, as were carnelian, feldspar, amethyst, turquoise and jasper ‚ many of the same stones we use today.

Glass was introduced as a component of beads around 1480, when Venice began drawing glass tubes and turning them into beads. Once the technology for pulling glass tubes was invented, it was easy to suddenly produce thousands of beads, all uniform in size, color and shape.

Modern jewelry and beading certainly benefits from the advances made in the production of beads, but there’s no doubt that even today, an individually handcrafted bead can be the star attraction of any beading piece.

Author : Felicity Walker

Beads can be strung together in any number of combinations to create different objects. Most of the times we create ornamental items like bracelets, earrings, and so on. Accomplished beaders are known to create highly complex bead items like multi-strand necklaces and complete ornament sets.
Beads come in a huge variety of shapes and sizes and styles. Some well known types include: Delica beads (cylindrical and very symmetric), opaque beads (non-transparent, single color), donut beads (donut-shaped beads in various colors), Aurora Borealis beads (multicolored, also clear or opaque), galvanized beads (with a metal coating), seed beads (small beads that make the body of the ornament or that fill the spaces between the bigger beads), transparent beads, silver lined or gold lined beads, matte finish (dull coating) beads and more.
Beads are made from almost any possible material including stone, glass, metal, wood, semi-precious and precious stones. Select the materials based upon the design and the item that you are planning to make. When selecting beads, look for uniformity in the finishing and the ease of stringing them together as the main factors in your purchase.

Source : http://www.jewelry-thailand.com/