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Roger Weller, geology instructor

October Birthstones
by Bertha Hernandez
Physical Geology
Fall 2017

                                                October Birthstone

     Ever wonder why so many people wear colorful gemstones jewelry around their necks or in their fingers?  “The idea of birthstones-a gemstone assigned to each month of the year is thought to be an ancient one, and scholars trace it back to the Breastplate of Aaron that was described in the book of Exodus in the bible” (The history of Birthstones). Just like jewelry birthstones have been around for a very long time.  “The idea of each person always wearing a gemstone corresponding to the month of their birth is distinctly modern idea that scholars trace to 18th century Poland, with the arrival of Jewish gem traders to the region” (The History of Birthstones).            






What is Opal?

     According to, an Opal is a mineral, an amorphous form of silica, SiO 2 with some water of hydration, found in many varieties and colors, including a form that is milky white.

What is Tourmaline?

“Any of a group of silicate minerals of complex composition, containing boron, aluminum, etc., usually black but having various colored, transparent varieties used as gems” (Dictionary).

The characteristics of Opal

October birthstone not only has one but two birthstones. The birthstones for October are opal and tourmaline.  The opal birthstone is very beautiful.  It is not just one solid color like many other birthstones.  It is very unique because of its rainbow color. The uniqueness of this birthstone makes it more popular than the tourmaline.  “The crystal Opal is transparent with a bright spectrum of colors, while the fire opal is translucent with bold hues of yellow, orange, and red” (Birthstone Zodiac). The opal birthstone is very eye catching and beautiful. The opal birthstone has been around for a very long time. “Some records indicate that opal may have been discovered in parts of Northern Africa in 4000 B.C.” (October Birthstones: Opal and Tourmaline).



The characteristics of Tourmaline

     Tourmaline is the second birthstone of October.  People that are not born in the month of October aren’t aware that there are two birth stone for this month. “Tourmalines are a relatively recent discovery” (Birthstone Zodiac).  If someone is on the search for an October birthstone like opal, and if it’s not available they have the option to purchase a tourmaline birthstone instead. They are both beautiful birthstones even though both are very different in color. “Tourmaline display a wide spectrum of colors from yellow, blue, pink, red, green, black, band brown” (Birthstone Zodiac). Tourmaline is not just one solid color there are many gemstone colors that are considered to be Tourmaline. Thanks to the variety of colors available the buyer will have plenty of choices.





What to do with Birthstones?

Many people wear their birthstones in a gold or sterling silver necklace, while others also wear their birthstone in a sterling silver, gold or white gold ring.  They are so many different types of jewelry where they can add any birthstone to it. For example, earrings, toe rings and bracelets.  Other interesting pieces are body jewelry, for example, belly rings and even watches can have birthstones engraved on them.

Symbols and Meanings about October Birthstones

People don’t just purchase these birthstones because of the birthstone color. Yes, the colors on these birthstones are amazing.  For many years, birthstones have had a special symbol behind them. “The Opal was a symbol of and hope to the ancient Romans” (Birthstone Zodiac).  Tourmaline as the Opal birthstone also had its own unique symbol.  “Tourmaline is known as the ‘Peace Stone’ “(Birthstone Zodiac).  Birthstones are very special and important to people because of what they mean.  Many people in their families have different believes regarding the birthstones.  Some people think that tourmaline will help get rid of negative vibes and toxic people.



The Value of Opal and Tourmaline

     October birthstones have different values “Similar to colored diamonds, opals with higher color intensity are far more valuable” (Tourmaline and Opal Birthstone - October Birthstones).  The value on the birthstones ranges vary. For example, the size, shape, color all make a significant difference on the price. Like for the tourmaline the color makes a huge difference on how much is going to be worth. “The pink and green stones are less expensive as they are easily available while the neon-blue stones, knows as ‘Paraiba’ are expensive as they are rare” (Birthstone Zodiac).



Where can you find the October birthstones?

     Ever wonder where opal and tourmaline come from?  Even though, they are both October birthstone they are found in different locations.  “Tourmalines are commonly found in Brazil, Africa, the Middle East, California and the Maine in the United States of America” (Birthstone Zodiac).  Like the Tourmaline Opal is also found in Brazil, but not just in that country it is found in other areas.  “Most of the world’s Opal deposits are found in Southern Australia, Mexico, Czechoslovakia and Nevada” (Birthstone Zodiac).  



Where to purchase Opal and Tourmaline?

      Birthstones are now found in most jewelry stores. The best place to purchase an opal or tourmaline will be at a gem exposition show. Those exposition shows have experts that can help you find exactly what you need, and answer all your questions.

How to Take care of your birthstones

     Since October birthstones are very expensive, they need to be well taken care of.  Opal and Tourmaline should be washed with warm water and soap, but preferably they should be taken to a jewelry store and be cleansed by a professional.  If they are not properly cleaned they make become damaged.  Opal should not be left in the sun for a long time. The heat will lead to cracks or fractures.  When a gem becomes damaged the value is dropped from what it was originally purchase for.





Work cited pages


October Birthstone

The History of Birthstones

            Birthstone Zodiac

October Birthstones: Opal and Tourmaline

Tourmaline and Opal Birthstone - October Birthstones


Opal Photos

            Tourmaline photos

Opal picture #2

            Opal Picture # 3