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male thread

See:pin thread

maletra furnace

A hand reverberatory furnace for roasting finely divided ore entirely
without the aid of extraneous heat. Fay

malignite

A mafic nepheline syenite. Fifty percent of the rock is composed of
aegirine-augite; the remainder is nepheline and orthoclase in about equal
amounts. Accessories include apatite, biotite, titanite, and opaque
oxides.

malinite

An aluminous variety of halloysite.

malinowskite

A variety of tetrahedrite that contains lead and silver.
Standard, 2

mall

Eng. A heavy hammer. A drawing or prop mall is a long-handled mall used
when withdrawing timber. SMRB

malladrite

A trigonal mineral, Na2 SiF6 . (Not mallardite.)

mallan

Soft turf containing lumps of ore, Derbyshire, U.K.

mallardite

A monoclinic mineral, MnSO4 .7H2 O ; melanterite group. (Not
malladrite.)

malleability

a. The characteristic of metals that permits plastic deformation in
compression without rupture. See also:plastic deformation
ASM, 1
b. Minerals are malleable when slices cut from them may be flattened out
under a hammer. Examples are native gold; silver; copper; platinum.
Nelson

malleable

a. Said of a mineral, e.g., gold, silver, copper, platinum, that can be
plastically deformed under compressive stress, e.g., hammering.
AGI
b. A mineral that can be sliced and the slices hammered flat without
breaking, e.g., gold, copper. CF:sectile; flexible.

malleable cast iron

A cast iron made by a prolonged anneal of white cast iron in which
decarburization or graphitization, or both, take place to eliminate some
or all of the cementite. The graphite is in the form of temper carbon. If
decarburization is the predominant reaction, the product will have a light
fracture, (whiteheart malleable); otherwise, the fracture will be dark
(blackheart malleable). Pearlitic malleable is a blackheart variety having
a pearlitic matrix along with, perhaps, some free ferrite.
See also:iron

malleable mineral

A mineral that may be flattened or deformed by hammering without breaking,
for example, native copper or gold. Stokes

malleable nickel

Nickel obtained by remelting and deoxidizing electrolytic nickel and
casting it into ingot molds. It can be rolled into sheet and used in
equipment for handling food, and for coinage, condensers, and other
purposes where resistance to corrosion, particularly by organic acids, is
required. CTD

malleablizing

Annealing white cast iron in such a way that some or all of the combined
carbon is transformed to graphite or, in some instances, part of the
carbon is removed completely. ASM, 1

malleate

To shape into a plate or leaf by beating or hammering; said of metal.
Standard, 2

malmstone

a. A hard, cherty, grayish-white sandstone, specif. the Malmstone from the
upper part of the Upper Greensand (Cretaceous) of Surrey and Sussex in
England, used as a building and paving material. AGI
b. A marly or chalky rock. AGI

malpais

A term used in the Southwestern United States and Mexico for a region of
rough and barren lava flows. The connotation of the term varies according
to the locality. Etymol: Spanish, mal pais, bad land. AGI

maltesite

A variety of andalusite, resembling chiastolite, showing in cross section
a maltese cross of pure material separated by areas of impure material.
English

maltha

a. Various natural tars resulting from the oxidation and drying of
petroleum. See also:mineral tar; pittasphalt. AGI
b. A black viscid substance intermediate between petroleum and asphalt.
Also called malthite. Webster 3rd
c. A variety of ozocerite. Webster 2nd

malthacite

A scaly, sometimes massive, white or yellowish clay related to fuller's
earth, having a Si-Al ratio of about 4. AGI