Marius, that's a maybe yes, maybe no thing. Scratching I mean.
For gemstone testing we use picks of varying hardness.
The generally accepted MOHs hardness for jadeite is 6.5 to 7
The generally accepted MOHs hardness for nephrite is 6 to 6.5
Individual specimens of both minerals can test higher or lower
I have a range of picks that I bought as a set, but the one I carry when I'm cruisin' with money in my pocket tests for 6.5.
That 6.5 test pick has not to date managed to scratch nephrite, and it won't go anywhere near jadeite.
6.5 MOHS is something like mid-80's Rockwell --- maybe 85 or 86 Rockwell
For comparison, a table knife is about 56-58 Rockwell, a decent hunting knife or pocket knife is about 59-62 Rockwell.
In Australia there are good deposits of nephrite in South Australia, and across in New Zealand it is also reasonably common. I've seen a photo of a lump of nephrite in Canada that was as big as a house.
A mineral that is very often presented as, and mistaken for nephrite is serpentine, a lot of Northern Indian daggers that supposedly have jade hilts are in fact serpentine. This has a MOHs hardness of MOHs 3 to 6, so at the top of its range is almost indistinguishable from nephrite at the bottom of the nephrite range.
With gem quality Jadeite, the stuff that is used for rings, rather than bracelets, the best stuff supposedly used to come from Burma (Myanmar).
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