What do I look for when buying Verdelite (green) Tourmaline?

Verdelite Tourmaline is probably one of the most common and used gemstones available in the market today. Like all Tourmaline, Verdelite sets and wears well in almost any jewelry.

Keep in mind that these are my personal opinions and experiences, other people may have different ones.

For gemological and cutting information on Tourmaline

Color - Verdelite is basically green Tourmaline. Any shade from yellow/green to green/blue (more green than blue). There are many colors and green Tourmaline is probably one of the most common colors as well as the most commercially available color. Mint (think Andes dinner mints) color is probably one of the most valuable colors.

Note: Chrome Tourmaline is considered the top green color of all green Tourmalines. It is listed on a separate page because it is chemically different then Verdelite and really a subject of it's own.

What do I look for when buying Chrome Green Tourmaline?

So how do I define Verdelite? OK, here is my working definition. The stone in question (Tourmaline) can be any shade or color as long as when you look at the stone it is more a shade of green than any other color.

Note: As Verdelite becomes green/blue to blue/green it will gradually be called Indicolite. This is a judgment call (the stone should be more blue than green to be called Indicolite), but in many cases people will try to call a green/blue stone Indicolite because blue brings more money in the market.

Clarity - High clarity IF to VVS stones are rare, but available. Of course the lower clarity material is more readily available in the commercial market, but better quality and clarity can be found. High clarity IF to VVS stones are available in the high end commercial market and the American quality cut market (look at my cut stones you will see them).

Treatments - Generally green Tourmaline is natural and has very little treatments. Heat is about the only thing that is ever done, and in general heating green Tourmaline is not all that common because heat usually does not work.

How does a buyer protect themselves from undisclosed treatments? The first line of defense is deal with a quality, experienced gem dealer with a good reputation. Dealing with some one that is an honest and experienced gem dealer is the best way to go.

How does a buyer protect themselves from undisclosed treatments and substitutions (fraud)?

Tips for Spotting Treatments - Green Tourmaline is rarely treated, with the exception of heat. Heating can usually be easily spotted in the rough, but once cut is difficult to tell with out a lab test.

Durability - Tourmaline of all types has good durability and can be set in about any type of jewelry. The only exceptions are stones of low clarity (read that as having flaws) that maybe weakened because of their flawed structure.

Sizes - Verdelite Tourmalines are available in about any size range, depending on your budget. 1 carat to 6 carat stones are not difficult to find. 8 carat to 15 carat stones are around and can be found, although not plentiful. Over 15 carat stones are available but generally more upper end or the collector market. I have cut top quality Verdelites well over 100 carats in finished weight. So they are available.

Cuts & Styles - Verdelite Tourmalines are available in about any cutting and style. I find as the stones become more saturated in color (larger) that brilliant cuts and checker boards work best. If the stone is not too dark about any type of cut you like can be done.

Cutting Quality - Is the stone cut to high custom standards? Or is the stone cutting the normal commercial quality? Cutting is very important and significantly effects the value of the finished gem stone. If the stone is a high quality cut and particularly cut by a well known cutter it will increase the stones quality and value, many times as much as double or more.

Note: There are also different levels of commercial cutting. Some commercial cutting while not any where near the standard of top quality (like mine), is significantly better than low quality commercial cutting. A sign of good quality commercial cutting is that the stone is symmetrical and the proportions (table, crown, pavilion) are correct and the stone has a good polish and reflection.

Commercial Market (trade) - Green is about the most common color of Tourmaline and in general the lighter and brighter the color the more valuable. Mint green is probably one of the most valuable colors.

Origin - To some collectors knowing the origin of a gem stone is important and some times it does effect the value of a stone, but usually not in Verdelite. In most cases it does not really matter where the stone came from other than is is nice to know where the stone was mined.

Value - High quality Verdelites (mints, teals, light colors) are increasing in value and I think will continue to do so. There is never any way to be certain but the way the gem stone market is trending just about any quality stone will appreciate.

Collectability - Collectors discovered Vedelite early on and quality greens and mint Tourmaline, particularly of decent size are sought after and bring more money than almost any other color.

Questions to ask when buying

Is the stone natural or man-made? - There is no man-made Tourmaline, but I have seen some substitutes in the market from time to time. This is always a good question to ask.

What is the clarity of the stone? - I would only recommend stones that are IF to VS in Indicolite Tourmaline. Be aware of the different and some times miss leading grading systems some labs and sellers use.

Is the stone heated? - Heat is some times used to lighten the color of Tourmaline or some times eliminate an unwanted secondary color or tone. I have no issue with heating as stone as long as the information is disclosed. Some purists want only a natural "unaltered" stone. This is a personal decision.

Is the stone heated and Irradiated? - Like I said, a lot of the commercial Indicolite available is heated and some are irradiated. I do not mind the heat, but when you are irradiating a stone you are putting color in that was never there in the first place. I generally do not sell or recommend irradiated stones.

Note: Heat only modifies the color of a stone, lightens or heats out an undesirable color. It does not put some thing into the stone that did not already exist. Heat is some thing that happens in mother nature, so I personally do not find it that much of a problem.

E-mail to inquire or order: jeff@faceters.com