2010年7月28日星期三

Precious gemstone jewelry will last a life time.

p until the end of the 19th century yellow sapphire was known as ;oriental topaz; only blue (corundum) was called sapphire.Rubies and sapphires are classed as (corundum) where as emeralds are something completely different, emeralds are classed as (beryl). Medium to dark green variety of beryl is highly valued as a gemstone, most emeralds are flawed and cloudy, a flawless emerald with good color is one of the most sought after and command high prices. Rubies may be in any shade of red, from pinkish to purplish or brown red but the finest ruby is best described as the colour of pigeon blood. All natural rubies have imperfections in them, including color impurities and inclusions to a trained eye the presence of these imperfections distinguish a genuine ruby from synthetics. All most all rubies are treated in some form, heat treatment is the most common practice, however rubies that are of excellent quality and are untreated command a large premium.Sapphire, all gem quality (corundum) that is not red is called sapphire, this name is associated with the color blue and is highly prized as a gemstone. Normally ranges from very pale blue to a deep indigo but the most valuable is a clear, deep blue, some stones called ;colour change sapphire;, exhibit different shades of blue in natural and artificial light. Sapphires also come in many other colors, colorless, yellow, pale pink, orange, green, violet and black, they are called fancy color sapphire.