MAGNESIUM AND MAGNESIUM
COMPOUNDS
By Deborah A. Kramer
Ms. Kramer is a physical scientist with the Branch of Industrial Minerals.
She has covered magnesium and magnesium
compounds for 10 years. Domestic survey data were prepared by Wannette Davis,
statistical assistant; and international data
tables were prepared by Amy Durham and Dave Mann, international data coordinators.


U.S.  primary   magnesium  metal
production declined slightly in 1993 and
imports, primarily from Russia and
Ukraine, provided an increased
percentage of domestic demand.  In
addition, inventories of magnesium
increased significantly from the low level
at the end of 1992. These increases in
inventories and imports prompted two of
the three U.S. producers to announce
cutbacks in production rates near the end
of 1993. This oversupply situation was
reflected in free market prices for
primary magnesium during the year.
Prices dropped steadily through the first
three quarters of 1993 before rebounding
slightly during the last 3 months.
In the past few years, automobile
manufacturers have begun designing
magnesium alloy diecastings into future
car models.    Many of these new
components have been introduced in the
1994 model year and as a result,
consumption of primary magnesium for
diecastings has increased significantly.
This is expected to increase as
magnesium continues to be specified by
designers for more components.
In Europe, a producers' association
filed an antidumping complaint alleging
dumping of magnesium on the European
market by the former U.S.S.R. Other
countries, including Japan and India, also
have suggested that magnesium exports
from the former U.S.S.R. have adversely
affected their magnesium production.
Several magnesium production facilities
in Japan and Europe were either shut
down completely or closed for a short


period during 1993. At the same time,
construction of new facilities in Australia
and Israel was proceeding on schedule.
U.S. production of magnesium
compounds from all sources (magnesite,
dolomite, seawater, brines, and olivine)
continued to decline as it has each year
since 1988. Domestic demand, however,
increased by nearly 8 %. The increase in
demand was met primarily by increased
imports, particularly caustic-calcined and
dead-burned magnesia from China. U.S.
producers were concentrating on
increasing production of magnesium
compounds for use in environmental
applications such as acid neutralization.


DOMESTIC DATA COVERAGE


Data for magnesium metal are
collected from two voluntary surveys of
U.S. operations. Of the 113 companies
canvassed for magnesium consumption
data, 73% responded, representing 46%
of the primary magnesium consumption
shown in tables 4 and 6. Data for the 30
nonrespondents were estimated based on
prior-year consumption levels and other
factors.
Data for magnesium compounds were
collected from one voluntary survey of
U.S. operations. Of the 19 operations
canvassed, 84 % responded, representing
75 %  of the magnesium   compounds
shipped and used shown in table 13.
Data for the three nonrespondents were
estimated   based   on   prior-year
consumption levels and other factors.


BACKGROUND


Definitions, Grades, and Specifications
Primary magnesium metal contains a
minimum of 99.8 % magnesium.
Magnesium-base alloys are named by the
composition of the two chief alloying
elements, each designated by a letter, and
the approximate percentage of each
alloying element. For example, AZ91
contains about 9 % aluminum (A) and 1 %
zinc (Z), and HK3 1 contains about 3 %
thorium (H) and 1 % zirconium (K).
Other  letters  used  in   specifying
magnesium alloys are E for rare-earth
metals and M for manganese.
Magnesite, or magnesium carbonate
(MgCO3), has a theoretical magnesium
content of 47.6 %. Dolomite is a calcium
carbonate-magnesium carbonate mineral
(CaCO3OMgCO3) that has a theoretical
magnesium  content of 22 %. Brucite,
magnesium hydroxide [Mg(OH)j],
contains up to 69 % magnesium, and
olivine (Mg2Fe2SiO4) contains up to 19 %
magnesium.      Of   these  minerals,
magnesite and dolomite are the largest
sources of magnesium and magnesium
compounds.
Seawater,  brines,  and   bitterns
represent vast sources of magnesium and
magnesium compounds. In the United
States, more than 60% of the magnesium
compounds produced annually is
recovered from seawater and brines, and
80% of the magnesium metal production
capacity uses seawater or brines as a raw
material.


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MAGNESIUM AND MAGNESIUM COMPOUNDS-1993