Corundum (a.k.a. Sapphires and Rubies)

The minerals in the following pictures were soaked in vinegar, then scrubbed with water and baking soda.  The first picture of the vibrant blue sapphire has not been cleaned with anything.

Corundum is the mineral group that Sapphires and Rubies belong to.  A ruby is red corundum, and sapphire is every other color of gem quality corundum.  The blue variety of sapphire is called sapphire, while the other colors (except red!) are referred to as "fancy colored sapphires".  Light red and pink corundum are also sapphires, not rubies.  For industrial use, corundum is also used as an abrasive called emery.  

Parti-colored and Chatoyancy or Asterism

Because of their popularity and value, there have been many schemes involving enhancement treatment of the gemstone to get either more weight and/or better color quality from naturally poor quality gemstones.  I don't want to talk to much about that right now.  Sometime this winter I plan on publishing a post to this blog explaining some of the processes involved in enhancing corundum for the gem market, including the ethical heat treatment of gemstones, as well as such scams as laser drilling holes in diamonds and rubies, which are then filled with glass.  Buyer beware!

Most of the sapphires I've found are purple, or as a lot of people say, lavender.  Some are parti-colored (multi-colored), and I am certain that some are going to be star sapphires.   With only my 10x loupe, and without being able to polish them, I have been able to confirm the rutile needle inclusions that make the asterism (star) effect in one of the stones, however; I am certain more will display this after being polished.  I am also not ruling out the phenomenon known as "color change", meaning that in daylight, they are one color, and then under incandescent light they change a different color.  It is not common, but so far these rough stones are possible candidates.  

Black Star Sapphires

I have also recently found a spot with "black star sapphires".  If you do a search on the internet for "black star sapphire", you will see some awesome looking gemstones.  The "star", also known as "asterism" is caused by parallel rutile needle inclusions running in 3 different directions.  Black Star Sapphires can exhibit 6 and 12 ray stars, also referred to as "arms".

This one has really got me asking questions.  Is it a pseudomorph?  It also appears to have both pinkish purple and blue colors.

Prospecting Adventure (an introduction)

The Salmon River in Idaho, USA

My name is Michael Brandon, G. G. S.  I am certified as a Graduate of Gemological Sciences from the Texas Institute of Jewelry Technology - http://www.parisjc.edu/index.php/tijt/content/study-of-gemstones - my intention is to share information and continue to learn information about not just gems, minerals and the many opportunities they may provide;  but also to share the wonders and the rawness of the journeys that lead to that star sapphire, ruby ring, or sometimes just to witness the treasure of nature's beauty.  Ah, now there's a thought ...

I've spent this last spring and first half of the summer camping out in the "Gem State".   It was an unusually wet spring this year.  The creeks and river were flooding and at first I wasn't real sure where I should start to look for gems.  Don't get me wrong, I'd love to find some gold, too.  I talked to some people in the various towns and communities about places that would be good to look for gems and tried to figure out what exactly could be found.  For the most part, people have been encouraging and informative.

Purple (possibly "Star") Sapphires from my first "dig".

Now that the rains have died down I have been digging, with permission, in the tailing piles of an old gold mine and at various other places within an hour's drive of where I am located.  I do not have my lab equipment for identifying gems and minerals yet, so I have found interesting specimens of as yet unknown identity.  Most of the specimens are simply found on top of the ground.  I was told that a lot of prospectors who have come through this region were only looking for gold, or just didn't know what the other minerals and gems were.  I have found  small pieces of "golden", pink, blue, purple, and star sapphire; a variety of garnets, serpentine, calcite, a nice piece of jasper, blue chalcedony, small and large clear quartz points, and a quartz point that appears to turn from smoky to citrine.   I have also found nice specimens of mica and other as yet unidentified minerals.  Later, when I have tested everything, I will update the unidentified minerals with their proper identification.

Blue/Pink/Purple/"Golden" Corundum.  Yay! Starting to get a little bigger!

Beautiful vibrant blue sapphire "chip"

Purplish pink sapphire

Vibrant pink sapphire chip

One great thing I have learned about prospecting is that when you are on your hands and knees in the dirt you begin to notice many different things besides rocks.  I have enjoyed learning the characteristics of certain insects and animals.  I have started to learn more about edible and medicinal plants since I have started camping and hiking more.  My conversations at the coffee shop have started to turn into mineralogy and mining study groups.  I finally figured out how to harvest some nice morel mushrooms.  Well, you get the picture.

A small Butterfly colony

Interesting Mushrooms with strawberries

I'm deepening my knowledge about indicator minerals for gemstones as well as geological formations and interactions.  There are limestone, granite, and basalt coming together in many places here.   I am collecting micro mineral specimens, and will be putting together some kind of website for my mineral collection in the future.  I am also interested in faceting and lab work.

You never know what I may be able to "gather" for you.  One thing I have learned, is that only reported minerals of specific locations are researchable through non-local resources.  In other words, not all found minerals have been reported to the government or mineral societies.

The first few posts in this blog may be a "catch up" of some of my recent prospecting adventures.

Enjoy!