SUCCINITE/AMBER/WHEELERITE -or WHATEVER
                By Merrill O. Murphy, with dopping advice from Scott Wilson.

General Succinite? Wheelerite? Who ever heard of such minerals? Strange as it may seem, succinite seems to be the official mineral name of “true amber.” Wheelerite is the name applied to an “amber-like” mineral found in the coal fields of northwestern New Mexico.

All types of amber exhibit an “amber color”. They appear also in pale to bright yellow, milky yellow, orange-yellow, and brown or brownish-red. Amber is generally transparent, but inclusions of various debris or countless tiny bubbles may leave it merely translucent.

That only marks the beginning of a mineral nightmare surrounding amber. Amber is found in scattered areas around the world. In small quantities, it appears in various parts of North America and in the Caribbean Islands. There may be small differences in the chemical makeup of the various “ambers”, and several of these sport local names.

The far northern cape of Alaska, Point Barrow, has produced small pieces of amber. The Eskimos find it washed up on the beaches and call it “auma”, meaning “live coal” in their native language. A similar material from a Kansas location is called “jelinite” after George Jelinek, who first found it. Fairly large quantities have come from Manitoba, Canada, on the southwest shore of Cedar Lake, where it is called “chemawinite” or “cedarite”.

Still farther to the northeast, amber has been reported in Greenland. Amber found in Sicily is called “simetite,” that from Myanmar (Burma) is “burmite,” and amber from Romania is “romanite.” Small bits of amber are sometimes pressed together at just under melting temperature, which is called “amberoid.”
So, what really is this stuff called by so many names? Chemically, amber is a hydrocarbon, running about 75% carbon, 10% hydrogen and 10% oxygen. These percentages vary somewhat depending on the source location. Amber is not a single compound, but is a mixture of several compounds, plus ingredients having no known effect on the mineral properties.

A major component of amber formation is a compound called succinic acid, hence, the mineralogical name, “succinite”. Most amber seems to have developed from the sap of an extinct evergreen tree similar to our American Thuja Occidentalis, better known as Arborvitae or white cedar. The juices of certain legumes also contain succinic acid and may have been the source of other amber or amber-like resins.

Amber and the amber-like resins are often termed “fossil resins”. I have a small problem with that term when applied to amber. To me, a fossil is a mineral in which some or all of the structure has been replaced by silica or some other mineral. If the external shape is retained in a replacement, but the internal structure is not, then that specimen is a pseudomorph after the original substance. Amber doesn’t fit either description. Ages ago, it was a gummy fluid so sticky as to adhere to everything that it touched. Then, along with wood and other vegetation, it was buried under many layers of soil, sand, gravel, and water. Under moderate pressure and temperature, the molecular structure slowly shifted to accommodate the changed environment. What had been liquid became a soft, but stable, solid resin. That is my understanding of its transformation.

But all amber-like resins are not exactly the same. They look alike. They cut alike. They soften at about 150 degrees C. and melt at between 250 and 325 degrees C. When set aflame, they all burn with a smoky, sooty flame and smell of pine forests.

The hardness of the various ambers falls in the range between 2 and 2 1/2 on the Mho’s scale. That means they are about as hard as your fingernail and about as tough and resistant to scratching. These ambers can be filed, hand-sanded, hand-polished, and engraved with steel tools. The specific gravity varies between 1.05 and 1.10, more or less, depending on the presence (or lack thereof) of included debris or lots of tiny bubbles. The refractive index lies close to 1.54, like quartz, and varies little regardless of the source. These various ambers are not crystalline and, therefore, exhibit no birefringence.

Amber can be faceted, cut en cabochon, or carved. Wonderful beads, both smooth and faceted, are made from amber, partly because it is so light in weight. Actually, the ambers will sink in fresh water and float in very salty water. This characteristic provides us with a very easy test for detecting imitations that sink in water no matter how salty.

So far, I have not mentioned one discernible difference between the various ambers or amber-like minerals. However, one strong difference does exist. “True amber” is not dissolved, to any extent, by alcohol. Wheelerite is readily dissolved in alcohol. Why, I do not know. Perhaps, a small chemical difference exists between ambers that dissolve in alcohol and those that do not. Perhaps, their widely different ages and their time spent underground result in a physical difference. Anyway, this one characteristic affects the way we clean all ambers. Since we have no certain means of determining which amber we have, we clean NONE of them with alcohol.

Areas along the southeastern shores of the Baltic Sea currently produce about 90% of the world’s gem-quality amber. The Dominican Republic in the Caribbean produces much of the remaining 10%. Most of that is brown to brownish-red.

Ambers as old as 120 million years are known. The Baltic amber seems to be between 30 and 60 million years of age, and amber from the Dominican Republic is younger still. Ambers of the United States and Canada range in age from contemporary with the Baltic material to considerably more recent than that from the Dominican Republic. The Baltic ambers are often referred to as “true amber,” suggesting in a snobbish way that other ambers are inferior or even not amber at all. That inference is untrue, of course, but the great age of the Baltic ambers may suggest that age has something to do with the solubility in alcohol regarding some of the ambers. The wheelerite of New Mexico is one of the younger ambers and is one of those dissolving readily in alcohol.

Amber is found only in weakly-compacted sedimentary formations, usually in association with lignite or other soft coal. Often amber contains partially decayed wood or other plant bits. If the amber had been subjected to greater compaction and/or any considerable temperature, then it would have been destroyed long ago.
Since this is an article for the New Mexico Facetor, it would seem appropriate, at this point, to include some New Mexico amber locations. There is probably some amber in all of the north and northwestern New Mexico coal veins. There even may be an occasional piece found on the dumps of abandoned mines in that area. However, there is no assurance that looking over the dumps of any of these mines will yield cuttable pieces. I certainly do not recommend entering any of these mines, especially the abandoned ones. Some amber found there will be wheelerite. If you care which you have, you might place a bit of it in a shot of vodka. If the amber dissolves in an hour or less, don’t drink that shot. It is wheelerite, and who ever heard of drinking tincture of wheelerite? Beyond this, I do not know a good way to tell which amber you may have found.

Locations:

Sinkankas (GEMSTONES of NORTH AMERICA, 1959) suggests: 1) the Sugarite Mine and the Yankee Coal Bed in the Raton coalfield of Colfax County, “abundant as large lumps and streaks”. 2) “amber-like irregular lumps in the Gallup-Zuni coals of McKinley County and abundant in the coal south of Devil’s Pass, twelve miles northeast of Thoreau and elsewhere in McKinley County”. 3) “Wheelerite is abundant in the coal of the Upper Cretaceous in the Rio Puerco field of Sandoval County”. 4) “in the Durango-Gallup field of San Juan and McKinley Counties”. Northrop in MINERALS of NEW MEXICO, 1959, gives similar locations while not mentioning the Raton area.

Sizing:

Most amber pieces will require cutting to size before faceting or other lapidary work. I suggest cutting with a sharp, thin diamond saw blade. Push the amber gently against the blade while maintaining a firm grip on the piece. It takes very little sideways pressure to fracture amber. Be very sure that the blade is getting copious amounts of coolant. If your saw has a vise or moving table, then use it. The blade may clog with some of the adhering amber bits. If so, brush the particles from the diamond-charged edge and return to cutting. Remember, amber is somewhat brittle and melts easily from friction-generated heat. Amber conduct heat very poorly and retain the heat at the point of generation.

Dopping:

This is one of the critical parts of the game. If you cannot dop your amber, then you cannot facet it or cabochon-cut small pieces. Low temperature dopping wax and stick shellac both melt at temperatures below the melting point of amber. However, both contract as they cool, thus stressing the brittle amber.
Another problem appears when the finished “stone” is removed from the dop. The safest way seems to be to place the dopped amber in a pan of water, add a little liquid detergent, and heat the pan of water to boiling. At this point, the amber may be slipped off the dop, with the adhering wax quickly wiped away using a soft cloth. I have used green dopping wax to dop amber for cabochon cutting, but I have never been comfortable with it. A little wax is bound to remain on the amber. Chipping it off with a knife or a fingernail may well result in damage.

Five-Minute Epoxy might do the trick, but I am wary of the strong solvents it contains. A better answer seems to be the “super glues” (cyanoacrylates). Use the smallest drop you can get from the container. Place it on the end of the dop chosen. Place the glue end of the dop against the flattened amber surface and press gently. Hold in a fixed position until the super glue sets, about a minute or two. The easiest way to maintain a steady, but gentle pressure is to use the transfer fixture. The amber can be set on a flat dop. The second dop, with super glue in place, can be locked loosely in the opposing position, then pressed down to meet the amber.

Cabochon Cutting and Carving:

Cabochons can be cut on fine-grit grinding wheels. Machine sanding with 400- or 600-grit belts is possible, but I prefer hand sanding. Carving can be done with small machine tools or hand tools. In either case, I like to polish by hand with a bit of tin oxide or Linde A on firm, wetted leather.
Facet Cutting:

If an amber piece is small, then rough-cut the pavilion facets with a 325-grit (or thereabouts) diamond lap. A well-worn 180-grit lap is more practical for larger pieces. Use a medium to low lap speed with a fast water drip rate. Pre-polish with a 1,200-grit diamond lap at a very low speed, retaining that fast water drip rate. Use a very light hand pressure.

Polishing:

Various texts recommend a wax lap for facet polishing. I do not own one, but they can be purchased through mail-order sources. Instructions are sometimes found for making them. However, the literature indicates that wax laps will cause considerable facet edge rounding. So, I tried all the old conventional laps and polishes. All produced poor, scratchy polishes. I finally went to my old technique of Trewax Brand paste floor wax on a hard, fiber-impregnated plastic lap. The polishing compound was Linde A sprinkled sparingly on and rubbed gently into the hard wax film. I polished at a very low speed with a light hand pressure and a fast water drip. It worked wonders and rendered a good polish with only minor edge rounding. I suspect that the same wax surface on a tin or lead-tin lap would yield even better results. For information on waxing a lap, refer to my article, “Prepolishing Gems” page 13 of the New Mexico Facetor September/October 1996. In that article, I described prepolishing using no water. When the waxing technique is used for polishing, a water drip is probably necessary.

Be adventurous. Try amber. In the words of that comedian, “Try it. You’ll like it.” I certainly do.

Transfer Dopping:

With super glue, transfer dopping of faceted amber is a little tricky but not impossible. Using the transfer fixture and super glue, attach the second dop as described above. Now the amber is cemented to two opposing dops but still in the transfer fixture. The dop originally attached must now be removed. Use hot water to do that little trick. Release the transfer fixture clamp from the original dop. Set the fixture, with dops in place, in a metal pan at least three inches deep. The original dop should rest against the bottom of the pan. The dop that is to remain in place will be pointing upward. Place the pan on a burner of the kitchen range, then pour in cool water to a level about 1/16 inch above the top of the original dop. Add a few drops of dish-washing liquid and heat the water to a gentle boil. Turn off the heat and let set for, perhaps, 10 minutes. Test for glue release VERY GENTLY until the lower dop drops free. If you apply any significant pressure, the dop will come free but with a flake of amber still adhering.