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NEWSLETTER SIGNUP


Grading Bulk Rough Materials

When mining begins the material being extracted is usually found in many different areas within quite a large number of acres. Different areas have different amounts of impurities in the ground leading to some areas having more pure materials and others having less pure materials. The mine owners spend very large amounts of money on test digs in different areas to determine where each grade of material is located.

When you purchase graded material it either comes from a specific area of a mine where that grade has been consistently found, or it has been hand sorted for quality depending on the material. Due to this, it is possible to order a specific grade and while getting the majority in the exact grade you purchased, you may receive a few pieces of material that are either nicer, or not quite as nice as expected.

Most mines base their grading first on color, which is the most important factor as determined by the GIA (Gemological Institute of America.) After color the other things taken into account depending on the material are the secondary characteristics of clarity (in the case of translucent rough), the ability to take a polish or shine, size, the amount of matrix present, and other qualities specific to the individual material being graded.

When photographed most material is normally wet prior to pictures being taken, especially with mine run and high grade mine run materials, so the top layer of dust is removed and you can see the natural colors and characteristics of the stones.  Depending on the type of material the sizes of the pieces may vary.  This is common with any natural material, and the pieces you receive with your order may be larger or smaller than the pieces pictured unless a size is specifically stated in the listing.

For the purpose of our items, if no grade is listed with our products, then the material should be considered a mine run grade material. Following are the grades you will find in our listed items:

1) "AAA+" or "EX" Grade - This is top notch material and it will be difficult to find anything better for the type of material purchased. If you are ordering cabbing grade, do not expect facet grade just because it is "AAA+". What "AAA+" cabbing grade means is that you are getting the best cabbing grade possible with a top color, clarity, ability to polish, etc. Very little material that comes out of mines is this grade, usually this grade is less than 1% of all material extracted from the ground.

2) "AAA" Grade - This is considered one step below the "EX" grade. It has exceptional color and clarity and is an extremely high qualtiy material. Like the "EX" grade, very little material that comes out of mines is this grade, and for most materials this grade only applies to less than 4% of all the material extracted from the ground.

3) "AA" Grade - This is one step below the "AAA" grade materials. It still has an excellent color and clarity and is a very high quality material. While it is more common than the "AAA" grade, this grade still only applies to less than 8% of all the material extracted from the ground.

4) "A" Grade - This is one step below "AA" grade and is the top of the three "common" grades of material. This material has a very nice color and takes a good polish. If it is a translucent material it will likely have some inclusions and not be completely clear throughout with some possible cloudiness. This is the material that for the average person will provide the best mix of quality for the price.

5) High Grade Mine Run - This is completely unsearched material that comes from an area of the mine where they have found higher grade materials, but the veins aren't consistant and they find lower grade mine run materials mixed in with an "A" or better grade product. To hand sort these materials would be very costly, so it is sold as a high grade mine run containing a random mix of "A" or better grade and "mine run" material. Depending on the lot received, it may contain more "A" or better grade or it may contain more "mine run" material as your parcel is scooped at random.

6) Mine Run - This is a completely unsearched material and the quality can vary greatly. Usually this material comes from an area of the mine where they have not found a lot of very high grade materials, but on occasion it is possible to find very high grade material in a random mine run scoop. With mine run material it is like an unsearched treasure hunt because you never know exactly what you are going to get!