More and more jewelry lovers have begun to collect antique and estate jewelry to add to their collection, travelling greater distances and paying higher prices.For the gem lover antique and estate jewelry offers a real testing ground for your skills.Don't be surprised to find imitation stones set in beautiful gold or platinum settings.  Never assume that because it is old or belonged to a rich family , that it is what it appears to be. Imitation was used  in the Roman times in the early century. There is different enhancement techniques,Dyeing was the oldest used to enhance stones for jewelry.Some stones that were dyed were jade, opal, coral, lapis and to a lesser extent,poor -quality star rubies, star sapphire, and emeralds. It was used to make the color deep and  worth more. Blacking was a technique used to alter the color. It was done by starting a sugar- acid chemical reaction that produces carbon to blacken the color, this was used on opals to make them look like black opals. Smoking is a technique used only on opals, an opal is wrapped in brown paper that is then charred. The charred paper leaves a thin dark brown coating on the opal to intensify its fire.Waxing is used to enhance star rubies, and sometimes star sapphires.It involves rubbing the stone with a tinted wax to hide any surface cracks and improve the color.Foil backing was one of the most clever techniques from the olden days and even now.It was often used with stones that had a closed back setting, what was involved was lining the setting with foil then setting in a clear or transparent stone on top of the foil, the foil would add brilliance and or change the color of the stone,a lot of times what was thought of as being diamonds was  glass with a foil backing.Foil backing was not restricted to diamonds it was used on other gems, sometimes a different color of foil was used to make you think it was not glass but was a  sapphire or a ruby in the setting. Piggy- backing Sometimes the foil backing had a special touch the top of the gem would be a genuine diamond and the bottom would be genuine but the middle would be foil.it was to create the illusion that the diamond was larger then it really was.One of the ways to spot a foil back gem is to see if the setting is closed. While not all closed- back settings concel some form of deception ,many do.A diamond tester can be used to show you if it is a diamond [used in most jewelry shops] Look at the piece with a jeweler's loupe if you don't know how ask the jeweler to show you and if he won't run don't walk out the door. When you look at the gem check out the back the top and the sides ask questions and demand answers, if it was treated ask how,and get everything in writing Ask if it is a natural gem or simulant or synthetic.A simulated gem is made by man but has no counterpart found in nature, it has no physical properties of the real gem. A synthetic gem while made by man  has been scientifically made to duplicate a gem that occurs in nature. Think of it as ice , ice outside made by nature ice cubes made by man same physical properties.Just because it is old does not mean it is real or there is any value to it.Check out everything  before you buy antique or Estate jewelry.Because sometimes what you think it is could end up being something that it is not.