Just to stick my neck out for 'Stales to use his jade ax, (or axe) I suspect that jade is in
some sense a composite, that tiny linear elements keep it from shattering.

Edie: Ain't the ;Internet wonderful! I found a site that corroborates my conjecture:
"
Type B jade, bleached, polymer impregnated jade. To distinguish Type B jade, you
need to know the structure of jade as well as the principle and procedure of the
processing of Type B jade. We know that the chemical composition of jade is
NaAlSi2O6, which is composite with columnar crystals and the interlocking structure
made it to be a very tough mineral stone.
Because of oxygenation and hydrolysis,
oxides such as iron, manganese and calcium are adhered on the surface and even
immerge into the interspaces between crystal, which turn the color of the jade into
orange, brown, black, or grew. These impurities influence the transparency, as well as
the color of the jade. The purpose of using powerful acid such as sulfuric acid and
chemical on the jade is to remove these impurities, improve the transparency and to
make the green color of jade uninfluenced by the varied colors (caused by the chrome
and iron ion), which make it more delicate and charming (the green color is the original
color of the jade which cannot be removed and affected by powerful acid). Sometimes
the acid is heated to increase its strength. After the jade has been chemically
bleached to remove impurities, it will then impregnated with polymer to enhance
translucency. Polymer is injected into the jade with the use of a centrifuge. At this
stage the jade is covered with hard and clear plastic like coating."