a. Soft sooty coal found in face and back slips or cleats; fine slack
coal. CTD
b. To reduce, as a metal, to a lower temper. Standard, 2
A pink variety of elbaite.
a. A notch cut in a timber to receive another timber. Zern
b. See:legs
A magnesian variety of chamosite.
A monoclinic mineral, Na3 (SO4 )(NO3 ).H2 O .
A method of carburizing open hearth steel that consists of treating the
molten steel with carbon in the form of charcoal, graphite, or coke.
Osborne
a. A specified day's work, usually at the coal face. See also:stint
Nelson
b. A task, or a fixed quantity of coal, agreed to be produced per shift
for a certain price. CTD
c. Scot. To work by the day. Fay
d. A north German name for meadow or moor peat buried under clay.
Tomkeieff
e. Peat formed from marine vegetation. Holmes, 2
Indirect illumination of stage of microscope, causing objects to be
brightly displayed by oblique rays against a dark background.
Pryor, 3
See:biotite
Any one of a group of rock-forming minerals that are dark-colored in thin
section, e.g., biotite, hornblende, augite. AGI
See:pyrargyrite
See:pyrargyrite
Crude, dark-colored sulfur containing up to 1% oil or carbonaceous
material.
A variety of lydian stone from Victoria, Australia. English
Eng. Increasing the amount of air in mines to prevent explosions of mine
gases. See also:dad
A chlorine-rich variety of hastingsite.
a. An appliance for damping out vibration. It consists of a piston
attached to the object to be damped and fitting loosely in a cylinder of
oil. See also:hydrabrake retarder
b. A similar device for closing the valves in a Corliss engine, actuated
by atmospheric pressure or by a contained spring. Webster 2nd
An instrument for testing the density of gases. It consists of a thin
glass globe, which is weighed in the gas or gases under observation, and
then in an atmosphere of known density. Osborne
Age determination of naturally occurrring substances or relicts by any of
a variety of methods based on the amount of change, happening at a
constant measurable rate, in a component. The changes may be chemical, or
induced or spontaneous nuclear, and may take place over a period of time.
AGI
A monoclinic mineral, CaBSiO4 (OH) ; gadolinite group; in cracks
and cavities in diabase or basalt; may be used as a minor gem. Also
spelled datholite. Syn:humboldtite; dystome spar.
a. The top or bottom of a bed of rock, or any other surface, on which
structure contours are drawn. AGI
b. Sea-level datum.--Pl: datums. AGI
c. Any numerical or geometric quantity or value that serves as a base or
reference for other quantities or values; any fixed or assumed position or
element (such as a point, line, or surface) in relation to which others
are determined, such as a level surface to which depths or heights are
referred in leveling. Pl: datums; the plural data is used for a group of
statistical or inclusive references, such as geographic data for a list of
latitudes and longitudes. See also:datum plane; geoid. AGI