• YourGemologist Community News

    by Published on 04-14-2017 10:28 AM  Number of Views: 1041 
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    After writing this newsletter, I realized that I got the title all wrong. Why? I'll tell you at the end. For now, let's consider something: How many amazing things do we see every day in gemology study that we totally take for granted? Beautiful works of creation that we have become so accustomed to seeing that we no longer truly appreciate the wondrous nature of the thing. Examples? Here are a few that you may have seen before but did not stop your fast-paced day to contemplate. Simple things that you may have seen hundreds of times....but did not really stop to think about. Pause that hectic day of yours for just a few minutes...
    by Published on 03-28-2017 11:34 AM  Number of Views: 8266 
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    Calcite. At left you see a calcite rhomb crystal. This one is often referred to as "optical calcite" since it is very clear, and allows light to pass through it very easily and with little or no interference from structural anomalies. Calcite has a unique optical property carried to the extreme. It can take a single beam of light and split it into two very distinct and very demonstrable light beams. What goes on inside this calcite crystal is the same thing that goes on inside double refractive gemstones, taking a beam of light and splitting it into two. In the case of colorless calcite, the beams are colorless. But in the case of colored gemstones, the beams can be of a variety of colors, which give us the amazing gemstones that provide us with 2 or more colors based on the light beams being split. Allow me to show this a bit more clearly below.
    by Published on 03-28-2017 01:49 PM
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    Everyone is used to the "ooohs" and "aaaahs" of seeing the amazing color changes of various gems and minerals when viewed under ultraviolet light. As we see in this calcite and franklinite specimen at left, the effects of fluorescent lighting on certain gems and minerals can be awe-inspiring. Beyond the "ooohs" and "aaaahs," however, are some very important uses for fluorescence in gemology, along with a couple of places where this same fluorescence needs to be avoided. Today, we want to take a tour of the good and bad impact that fluorescence has, particularly on diamond color grading. But first...let's look at some lab created emeralds and the impact seen on these.
    by Published on 03-28-2017 09:28 AM  Number of Views: 9271 
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    Based on a multi-million dollar advertising campaign by the 800 pound gorilla in this industry, there is a misconception that doing professional level gemology requires you to spend tens of thousands of dollars on education, and almost that much on gemological equipment. I hate to break it to those of you who, just like I did, spend that money with the 800 pound gorilla because in the end, this gemology thing is not some magical, mystical knowledge. As my good friend Dr. Bill Hanneman has been trying to tell us for decades, this gemology thing can be done with very basic tools if we just slow down and learn what we are doing. So today, I wanted to share with you what I believe is some pretty amazing gemology, done with a poor man's polariscope. Before we start a couple of notices: there are quite a few GIF files in this edition, so if anyone is prone to motion sickness you might want to take your pharmaceuticals before reading this. Also, before we look at our poor man's polariscope we should review exactly how the polariscope works. For that we, of course, turn to our poor man's graphics done on our 17 year old iMac Blueberry.
    by Published on 03-29-2016 12:31 PM
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    For those of you who missed the ISG Journey Thru Gemology last week, I thought we would offer a review today in preparation for tonight's special journey presentation on Maximizing the Refractometer Part 2. First, if you have ever wondered what a refractometer looks like with its guts out, just look at the image at left. Here is the inner workings of the ISG Refractometer. If you look closely at the lower right side you will see two screws with red coloring. These are your calibration screws and they must be in exactly the right position. If anyone has ever purchased one of those cheap US$90.00 (or less) refractometers on ebay and wondered why your readings were skewed, its because the company did not actually calibrate the refractometer...they just screwed the parts together and sold it on ebay. To get proper readings these calibration points must be carefully positioned and glued tightly.
    by Published on 02-24-2016 02:15 PM
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    The Tucson Gem Shows always amaze me for the wonderful people and gemstones I find every year, and this year was especially amazing and I have a lot of stories to tell you about the trip. One story stands out that I wanted to tell you first, its the story of the Navajo Ant Hill Garnets that I learned about from the wonderful folks at the Sid Tucker LLC booth at the GJX show. Alan Hodgkinson told me I had to go see them, and I found out later it was for both their Ant Hill Garnet and the amazing homemade cookies that they offered. For now, we will talk about the garnets. Out in the Arizona desert lands of the Navajo Nation, there exists, in fairly shallow deposits, beautiful pyrope garnets that are small enough to be carried to the surface by ants who are digging out new tunnels through the ground.
    by Published on 01-07-2016 02:27 PM  Number of Views: 8433 
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    It's one of the hottest items in the current jewelry market: black diamond. The very name conjures up dreams of exotic places and people. But what really is a "black diamond" and how do you know you are getting a true black diamond and not an imitation like created black moissanite? First, authentic natural black diamonds are rare. The conditions at which carbon crystallizes causes all of the carbon to crystallize. So the concept that black diamonds are made of uncrystallized carbon is not totally accurate, based on current scientific report. Most black diamonds are actually low quality diamonds that have been irradiated to create a very, very dark green color that appears black. Some are simply regular diamonds that are so heavily included that they appear black. Whatever the source, black diamonds are hot on the market and many have asked how to separate black moissanite from black diamond. Here are a few "tells" we have found that may be of assistance in the effort.
    by Published on 01-25-2016 01:18 PM  Number of Views: 10902 
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    2. ISG Research Reports
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    Before we begin this discussion I need to make two points very, very clear. The following report is only for one CZ Master Set manufacturer, and we offer no guarantee that you will get the same results from all manufacturers, and The following report is in regards to one CZ Master Set from this one manufacturer, and may not apply to other sets produced by this same manufacturer. How's that for a start? Well, it had to be put in here because the use of cubic zirconia master grading sets for diamond color grading is a huge black hole waiting for you to fall in if you don't keep in mind what you are dealing with. You are technically grading apples by using oranges. Perhaps not to that extreme, but pretty darn close. You are grading natural diamond colors using created cubic zirconia with created colors.
    by Published on 01-14-2016 02:37 PM
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    Each week I receive the newsletter from Bill Boyajian that is always full of valuable information for jeweler's success in the industry. This week was particularly special as it provided a list of exactly why jewelers should be expanding into colored gemstones for future revenue streams and profitability. I reached out to Bill and asked permission to offer our readers this excellent list, which he was kind enough to allow us to share with you. At the bottom of this page is a link to subscribe to his newsletter. I read it every week and make sure never to miss an edition. It is full of important information and tips on how to be successful. Below are the 8 Reasons Why Jewelers Should Stock Colored Gemstones from Bill Boyajian.