Monthly Archives: July 2010

A NEW FIND OF CLASSIC GREEN QUARTZ ON SERIFOS ISLAND, GREECE

The term prase (or prasem) is used to describe lustrous, cigar- and spear-shaped quartz crystals with green hedenbergite inclusions.  The prase found on Serifos Island, in the Cyclades islands in Greece, is considered the best ever found in the world; it is often aesthetically sculpted, with dramatic visual appeal.  Specimens from Serifos are featured in mineralogical museums around the world.

Museum Quality 6½" Olive Green Prase Quartz Crystals from Serifos, Greece

Originally, the varietal name “prase” was applied to a leek-green colored quartzite (a rock, not a mineral). Now it is simply a color descriptor for quartz: If it is sage- or leek-green, it is called “prase” – no matter what causes the color. The color of prase is caused by various green inclusions, more or less evenly distributed throughout the interior of the crystals. Quartz with chlorite inclusions, however green it may be, usually does not count as prase. The most common inclusions seem to be fibrous amphibole minerals like actinolite, or the pyroxene mineral hedenbergite. Since the fibrous inclusions interfere with normal crystal growth, prase crystals often have peculiar and characteristic shapes that are very helpful in determining the provenance of the specimen.

4¾" Prase Crystals with Hedenbergite Inclusions - Serifos Island

Prase is found at only a very few locations. The most famous ones are the Island of Elba, Italy, and the Island of Serifos, Greece, located in the south Aegean Sea. Other locations include Dalnegorsk, Russia, and Morocco.  Perhaps the best site in the world for green quartz is the quartz deposits of Avessalos, on Serifos Island. Other minerals found in this mine include hematite (sometimes in small rosettes), andradite and amethyst. Other notable localities for prase on Serifos include Mega Horio, Megalo and Mia Chorio. Serifos Island, located in the south Aegean Sea, represents a multiple mineralized district including intrusion-hosted skarn rocks that formed when magma of igneous rocks intruded into carbonate rocks.

Lustrous 3¾" Olive Green Prase Quartz Crystals from Serifos, Greece

Prase crystals from Serifos have a peculiar shape. They are elongated and rarely show individual rhombohedral faces at their terminations. Instead, the ends look like pointed or blunt bundles of many small crystals. The overall shape can be cigar-like, hourglass-like, or sharply pointed spears. The crystals typically sit on a grey-green matrix of hedenbergite (or, possibly, actinolite).

Shiny 2¾" Moss Green Prase Quartz Crystals from Serifos, Greece

In Tucson in 2008, I acquired a large lot of specimens from a Greek miner who managed to get the necessary permits & permissions to run a month-long, hand-scale mining operation at Avessalos during the summer of 2008. This fellow excavated the floor of the large, shallow cave where prase crystals had been found years ago. By the time he scraped bottom, there was nothing left to mine, and he had a bunch of really fine, new crystals from this old classic locality. I was told that the lot I inspected was the last of the crystals that could be mined – at least without drilling, blasting, and heavy equipment which would be cost prohibitive. So, considering the circumstances, I picked out all the crystals that I liked from the lot – the ones with sharp terminations, vibrant color, and aesthetic sculptural arrangements. We now have many of these available in sizes from small miniatures to cabinet specimens, and will be selling them until they are gone. And that, unfortunately, will be the end!

Because of their scarcity, and because of the unlikelihood of reopening any of the mines on Serifos, prase crystals from this locality are now considered to be classics, and are highly sought after by mineral collectors.  You can see some of the green quartz specimens we have available here in the Prase Quartz Gallery on our website www.treasuremountainmining.com.

Superb 2.5” Green Quartz (Prase) with Hedenbergite Inclusions - Serifos Island

ADVICE FOR BEGINNING MINERAL COLLECTORS

I started collecting minerals when I was 8 years old, then quit when I discovered girls at age 13. Later in life, my interest was re-kindled when my son Dan was playing in the field behind our house and found a chunk of glacial quartz with a vug containing crystals.   My original goal was to share this wonderful hobby with my three children, especially the part about going out in the woods and finding buried treasure. Gradually, this goal evolved, and I ended up being bitten hard by the mineral collecting “bug” (some would call it an addiction).  As my passion grew, I plunged in head first, and began building a mineral collection.  As I proceeded, I made a series of blunders, the results of which still plague me today when I open one of the drawers containing my old collection.  Unfortunately, I didn’t have a mentor – someone who could have steered me in the right direction, so that I could avoid the pitfalls which, in retrospect, seem so obvious today.  So, here’s the advice I have learned through hard experience, and that I wish someone had given me along the way.  I hope it helps you to build a collection of fine minerals and gem crystals that you will be proud of today, and that will still be a source of happiness and wonder in years to come.

Suggestion #1:
Always buy the best mineral specimen you can afford

I still have some old cabinets that are stuffed with $5, $10 and $20 specimens.  The vast majority have some damage of are only fair examples of the particular mineral.  Regrettably, they’re still only worth the $5, $10 and $20 I paid for them 25 years ago.  What if I had been more disciplined?  What if I had purchased one $100 or $200 specimen for every 10 or 20 of the inexpensive ones.  What if I had only purchased specimens of the best possible quality and condition?  Then I would have an impressive collection, with fine, captivating, impressive specimens that have appreciated in value, and will continue to do so.

Suggestion #2:
Set a budget, and have a plan

Many advanced collectors build their collection by creating a budget and a plan.  Start by asking yourself, how much do I plan to spend on specimen purchases this year?  Add up what you spent on minerals last year (you’ll probably be surprised by how much you spent!).  If you buy specimens for your collection solely based on what you have to spend at any particular moment, you’ll have some good specimens that were purchased when your pockets were full, and some poor quality ones purchased when money was tight. 

Once you have a budget, divide it by the lowest possible number of specimens possible.  So, if you have a $1000 budget for the year, see if you can bear the thought of buying just five $200 specimens, or ten $100 ones.  My impulse is frequently to buy a lot of lower-cost specimens, because it’s fun opening a box that arrived in the mail containing a bunch of new specimens.  That’s why it’s so important to have a plan and stick to it.  At the end of the year you’ll have fewer specimens, but if each one is carefully selected to meet a set of discriminating criteria, you’ll have added specimens to your collection that look a whole lot better than a bunch of inexpensive ones.

Suggestion #3:
Don’t buy damaged specimens

I repeat, don’t buy damaged specimens with damaged crystals! Forget the temptation to buy when you think you are getting a “good deal” at a low price.  Always examine each specimen you are considering buying for damage such as prominent “dings”, dead areas with no crystallization, or contact points where crystals grew up against something.

I used the word “prominent” above on purpose: the challenge is that specimens that are perfect, with absolutely no damage, may be beyond your financial reach.  In that case, pick specimens without obvious or distracting damage, such as a specimen with a single large crystal that has a damaged termination.  You may have to accept living with damage to crystals on the outside edge of a specimen, because a truly perfect specimen is 10-, 20-, or 100-times more expensive than you can afford.

This suggestion is vital if you want to improve both the quality and the long-term value of your collection.

Suggestion #4:
Do your research before you buy

Knowledge is the key to success in mineral collecting.  So use all the tools available to learn all you can about minerals.  Visiting mineral museums, reading books, and the internet are all fine ways to learn more about minerals.  I also suggest you subscribe to one or more of the popular magazines devoted to mineral collecting, including Rocks & Minerals, The Mineralogical Record, and Gems & Minerals. Also, join a local gem and mineral club to learn from visiting speakers, to socialize with local collecting “experts” (and to view their personal collections), to go on field trips, and more (the snack table is usually the most popular area for viewing “specimens” at my club meeting).

I fined that the internet is particularly useful tool for learning about minerals.  For example, take a look at the photo galleries on www.mindat.com, and compare specimens there with one you are considering purchasing.  This will give you an idea of the range of quality available, as well as what to look for in a particular specimen.

Anther consideration is, where does a particular specimen came from?  For example, do you know what locality produced the finest azurites of all time? The best dioptase? The most excellent vanadanites?  Doing your homework will help you focus on selecting specimens from the world’s premiere mines.  These are frequently referred to as “classic” localities, and fine specimens from these first-class sites are always in high demand.  Sometimes, even the best specimen ever found at a less well known mine may not be as good as even a second-rate specimen from a premiere locality.

Suggestion #5:
Always keep the labels

You may have heard this bit of mineral collector wisdom: A specimen with a label is a specimen with scientific importance; without a label, it’s just a pretty rock (or worse, an ugly rock!). When you buy from a reputable dealer, he or she should provide a label giving the species name, and information about the mine, state or province, and country where it was collected.  This little piece of paper is important.  Don’t throw it away!

Without a label, you have no way to distinguish a wulfenite from the famed Red Cloud Mine in Arizona and one from the less-well known Geronimo Mine, which is on the other side of the same mountain.

Collectors who purchase minerals for their metaphysical and healing properties, or for their beauty, often discard the labels because they don’t think they’re important.  When they decide to sell some of their specimens, they are dismayed to learn that a specimen is worth half or less than a similar specimen with the label.  When I evaluate a collection, I can sometimes recognize it as coming probably from a certain locality, almost no one can tell the difference between a smoky quartz from Brazil and one from Switzerland?

A label may also be an historic document, which can add significantly to the value of a specimen.  Think of the difference between a specimen from a particular locality with a Smithsonian label giving date acquired, whom it was purchased from, etc., and one from the same locality with an unknown collector’s label.

So whatever you do, keep your labels, whether in a separate box or with the specimen.  The label is a valuable record.  Antique dealers call this provenance, and your newly acquired specimen is definitely an antique!

Suggestion #6:
Catalog your collection
When I built my collection, I started cataloguing the specimens early on.  I printed out a unique number for each specimen, and glue it on with white glue.  Then, in an Excel spreadsheet, I recorded the following:

  • Number
  • Mineral species
  • Mine specifics (e.g., level 14)
  • Mine name
  • County, State, and/or Province
  • Country
  • When mined
  • When & where acquired
  • Price paid
  • Other details (previous owners, where it is in your home, fluorescence, weight, etc.)

Today, there are dozens of software programs available that will record all this information, and which also make it easy to do a search to see all of your azurite specimens, or all of the specimens in your basement display case.

Suggestion #7:
Develop a focus for your collection

Choices, choices, choices! There are over 5,000 known mineral species, and so many of them are so extraordinarily beautiful and exciting that it is common for new collectors to start off with a helter-skelter approach of buying whatever hits them as particularly attractive and striking.  I have heard these collectors called “lightning bolt collectors,” because they buy something whenever they are hit by the lightning bolt of “have to have it.”  That’s why it is important to focus on one or two key areas of interest when starting to build a collection. Fortunately, there are a nearly limitless number of focal points or “themes” that a beginning collector can pursue.  For example:

  • specimens of a particular mineral species (gold, tourmaline, etc.)
  • specimens of a particular size (very small, decorator size, very large)
  • specimens from unique mining localities/countries of origin
  • specimens all in one favorite color
  • specimens from a particular geographical area (e.g., your home state, the United States, countries you’ve visited, etc.)
  • specimens with a common element, such as silver- or copper bearing minerals

Suggestion #8:
Build a relationship with a trusted mineral dealer

Mineral dealers have the opportunity to travel to distant show, buy from miners in distant lands, and purchase collections for resale. This means they can be of invaluable assistance in finding unique mineral specimens which will fill the gaps in your collection.  Share your want list with them, and review their offerings regularly to see what is new.  If they are on the lookout for that “special” specimen you’ve been looking for, it can help you fill a hole in your collection which has been empty for quite some time.

To review our newest arrivals, click on the link to our website.

If you would like to send us your “wanted list”, here’s our email address: eric@treasuremountainmining.com.

Conclusion

Above all else, collecting minerals should be fun! Mineral collecting is an intensely personal hobby, and the specimens you select are a reflection of your own unique ideas about what makes a particular mineral specimen interesting to you.  Make sure every specimen you chose is a joy for you to behold.  Follow that advice and you can never go wrong.  And, if you would like our help in building a quality collection, we’ll be glad to advise you.