October Birthstone: Opal and Tourmaline

October Birthstone: Tourmaline and Opal
Zodiac Stones
Libra September 23rd-October 23rd: Chrysolite
Scorpio October 24th-November 21st: Beryl

Opal Specimens

Opal Specimens

Opals are famous for their colors, which cover the entire rainbow spectrum in brilliant flashes. Opals have a unique non-crystalline structure of submicroscopic silica spheres that are held together with silica and water. The ‘play of colors’ develops in volcanic cavities and openings as the silica hardens into an opal. Colors are added with the presence of different materials, yellow and red opals have inclusions of iron oxides, black, green, blue and red opals contain carbon and magnesium. Opals measure low to medium on the Moh’s hardness scale, coming in between 5-6, and are best cut into cabochons or carved into beads. Opals have a reputation for drying out, or becoming dehydrated, but only some of the lower gem quality has this problem. To make the most of opal materials, thin slices are cut and mounted onto a black onyx backing making a doublet. Additionally, a magnifying glass layer can be added to the top making a triplet. These layers help stabilize and improve the look of the stone as well as extending the raw material. Other types of opal are Mexican fire opal and Peruvian blue and pink opal, these rarely display the ‘play of color’, instead they have a milky soft color play with inclusions of clear watery opal.

Opal rough, ready to be made into cabochons.

Rough opals, ready to be made into cabochons.

The brightest and largest amounts of gem quality opals are primarily mined in Australia.  Other sources of opal include Nevada and Idaho, the Czech Republic, South America, and Ethiopia.  In late 2008, NASA announced that it had discovered opal deposits on Mars. In 1974, Pierre Gilson created the first synthetic opals that rivaled the natural, with a very regular ‘play of color’. These synthetic opals are not opal imitations but material containing some of the silica as an opal would with the addition of resins to harden.

Mexican Fire Opal beads

Mexican Fire Opal beads

Opals have a long history of being in and out of fashion; sometimes they are associated with good fortune and considered lucky. Other eras see opals much in disfavor, discoloring if the wearer is in bad health, opals worn by sufferers of the Black Death would discolor as the wearer had extremely high fevers, and dull as they passed away. The origin of the name ‘opal’ is even up for debate, some point to a Roman connection to the word ‘opalus’ while others choose the link to the Sanskrit ‘upala’ or the Latin ‘opalis’ meaning lucky stone. Opals are the talisman of thieves and spies as opals may confirm invisibly on the wearer. Opals are regarded as the stone that symbolizes hope.

pinkperuvianopal

Pink Peruvian Opal beads.

Tourmaline is also a stone of many colors: pink, green, yellow, brown, and black are all within the color spectrum of tourmaline. Its makeup is a complex aluminous borosilicate material with other metals mixed in to create colors. Tourmaline is trigonal, meaning its crystals form in a triangle, unique among common minerals. High on the Moh’s hardness scale, 7-7.5, it is a stone well suited to faceting as well as carving into beads. Tourmaline is a name thought to come from Sri Lanka, ‘”tourmali” meaning something out of the earth, and is used to describe yellow, green or brown tourmaline. Bi-color or watermelon tourmaline is highly prized, green with a transition to pink, resembling the cross-section of a watermelon. Tourmaline is piezoelectric, meaning will build and hold static charge if rubbed firmly against fabric or heated. Irradiation is often applied to enhance pink and red stones.

tourmalinestrands

Tourmaline bead strands.

Tourmalines are mined around the world, Africa, South America and the US, in Maine and southern California.

Tourmalines are separated into their color groups when used to promote metaphysical qualities. Green and watermelon are used to promote peace and harmony, green is especially helpful for restful sleep. Pink is associated with grieving or loss of love, eases pain and promotes compassion. Yellow is for the academic, and helpful in business. Blue tourmaline is used for inner peace and self-expression.

Using Opal and Tourmaline in your designs

Opal beads of true gem quality can be very pricy.  Fire opal, pink, blue opals are much less expensive and widely available. The rich red-orange-brown of fire opal is a natural mix with gold.  As opals are quite lightweight (compared to some gemstones) make multiple strands to really push the color and texture forward.

Tourmalines offer so many colors! Many strands come with the colors graduated from one color to the next, try to keep them in order for the most sleek use of all the colors. Or break up the colors into separate piles so each group is more monochromatic. Tourmaline looks especially good with oxidized silver.

About Emily Miller
Beads make me happy. I need to work with my hands everyday to connect with the artist within. Teaching others spreads the bead joy.....

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