lapis lazuli
Iolite generally has a blue color, and leans a little toward purple.
Sapphire
Zircon is a gemstone used in rings and other jewelry. Zincite is another stone used in jewelry.
Jasper is a stone used in jewelry. It comes in many colors including blue, red, orange, black, brown, green, gray, or yellow.
It will usually be cut and polished to be used in jewelry.
Quartz
Blue diamond jewelry can be used for any occasion and comes in a wide array of choices. You can purchase blue diamonds in almost any form of jewelry that there is. Such as earrings, necklaces, rings and even broaches.
Amethyst is a precious stone much like but not as popular as diamonds. It is used in jewelry such as rings, necklaces and bracelets.
To be used in jewelry, stones are generally cut and polished, using a variety of equipment and processes.
rumors of it being a "toxic" stone
a semi precious stone used in jewelry making
Jarosite is not used in jewelry as it is too brittle. The luster is also dull and it is usually a dark yellow or brown stone.