I received an excellent email from a lady reader of mine from Japan. She writes very well and it is very informative. I reproduce her email unedited as below. My reply will follow in the next post.
Peace. Thank you for your kind response through Facebook.
I hope you will get the photo attached therein. The second photo is of the bangle which was cracked (the photo was taken before the crack materialized).
I do follow your writings on JadeiteJade.com, and they have been very informative, thank you very much.
I would also like to enquire about the subject of black/charcoal jadeite. I recently purchased a black jade bangle. The seller said the bangle is made from pre-formed jadeite, not technically jadeite per se, but that its feel and look are those of your run-of-the-mill jadeite jade.
The information I found on black jadeite normally categorizes it into two, the black/charcoal/grey jadeite (generally opaque and classed into the lower end of jadeite unless of high quality; known as Black Chicken variety – 烏雞種) and the Inky variety jadeite (the mineralogical nomenclature classed it as Omphacite; 墨翠), which is considered true jadeite (and which is not exactly black but a very dark green viewed under transmitted light). I am just wondering if the above information is generally true?
Fascinatingly, I frequent a site which sold both black jadeite jade and a kind of black Burmese stone which looks like jadeite but not considered to be so as the hardness is lower.
So, I am assuming that the bangle I bought might actually be this black Burmese stone, but is there really a way to know aside from doing a battery of tests? Anyway, the seller was honest in describing his item as not being able to be tested as jadeite as the hardness is not within the range acceptable for jadeite.
What I am really interested to know is whether the type of Black Chicken/black jadeite currently sold on the market is true jadeite (most of the time), and can generally be categorized as such?
One info source I found basically states that the Black Chicken variety and Inky variety jadeite come from different roughs, and that the hardness for the Black Chicken variety is lower. One (a Chinese book) states that the opaque kind of black 翡翠 (Fei Cui) is actually not jadeite per se but some other thing altogether, and yet, it appears that those are classed under Fei Cui as well.
I read from your blog that the US considers only jadeite and nephrite as jade, but from a source from HK, it seems they consider `Fei Cui` to be three different types of material, Kosmochlor, Jadeite and Omphacite.
I would really appreciate your view on this, given the fact that so many different groups of minerals/stones are bandied about, and it just gets confusing for an amateur jade enthusiast such as myself (especially one without a gemology technical background).
Thank you very much.