I am in possession of three blue coloured tourmalines that I suspect are Paraiba tourmaline from Mozambique, I am aware that paraiba consists of copper and manganese, luckily I have already checked the stones for these elements and they have proved that they have copper and manganese, but I am not sure what is the specific amount of copper required in a tourmaline for it to be called a Paraiba!
Please help me understand are my stones paraiba because they already have cooper and manganese or do they have to have a certain amount so as to be called Paraiba Tourmaline?
Hi
From my experience, these look like normal green tourmaline and not paraiba tourmaline roughs from mozambique. Im not sure how you tested the minerals. I recommend getting a reputable lab certified if you really need exact information. Bellaphorn lab in Bangkok is a great please do check.
I am not located in those areas I am from Tanzania and the test that I did was through i am located in Tanzania so it is hard for me to go to Banglok right now, unfortunately we don’t have a member of G.I.A here but there are instruments and machines used to determine the mineral elements in any stone, it read that my stones have Copper and Manganese but there is no international proffessional that can help me here, by the way with all due respect but paraiba comes with varieties of colours so the blue-green colour shouldn’t alarm you, 95% of paraiba is heated to attain the perfect colour
From your experience or knowledge, have you ever come across this kind of topic, because my struggle is to know whether there is a specific amount of copper needed in a stone or any amount aslong as it is copper can be accepted as a paraiba tourmaline?
There is no universally acknowledged minimum amount of copper standard for calling a cuprian tourmaline a Paraíba tourmaline. However, here is how the Laboratory Manual Harmonisation Committee (LMHC) defines Paraiba tourmalines:
A paraiba tourmaline is a blue (electric blue, neon blue, violet blue), bluish green to greenish blue, green (or yellowish green) tourmaline, of medium-light to high saturation and tone (relative to this variety of tourmaline), mainly due to the presence of copper (Cu) and manganese (Mn) of whatever geographical origin. The name of the tourmaline variety ‘paraiba’ is derived from the Brazilian locality Paraíba where this gemstone was first mined.
So, by this definition, Cu and Mn must be present in some amount in the tourmaline, along with the specified hue, tone, and saturation.
This GIA article has data on the ranges of Cu and other elements parts per million weight based on a LA-ICP-MS analysis of 301 Paraiba tourmalines from Brazil, Nigeria, and Mozambique. (Table 2). These figures are not intended as Cu standards, but they can serve to give some idea of amounts you can find in these stones. (And could also help determine geographic origin).
Very good info Mr. Sanchez. I agree with you and I think that after a nice cut and the perfect heating procedures these 3 stones , specially the 2 in the left, will come out as very nice Paraiba tourmalines, since, apparently, the rough is very clean.
Thank you it has helped very much, I have gone and cut one of the stones to see how it will turn out, below are pictures of the stone after I had it cut but it has not yet been heated
Thank you it has helped very much, I have gone and cut one of the stones to see how it will turn out, below are pictures of the stone after I had it cut but it has not yet been heated
