85
percent, and Michigan operated only its one mine.'*''*' The
richness of copper ores mined in all the states is not
nearly what it once was. The average copper content of
domestic ores fell steadily during the past century,
from an average of 3 percent in 1880 to 0.6 percent in
1969. The copper situation deteriorated so greatly that
a quota of 50,000 tons was established in 1968 on the
export of copper refined from domestic ores and a similar
quota of 60,000 tons by copper content of scrap also was
. 12
m effect.
At about the same time as copper was first taken
from the Upper Peninsula, iron was discovered in the same
area, a little to the south and east, around what now
is the town of Marquette. The Soo Canal was completed
in 1855 and in August of that year the first ore
shipment was sent down Lake Michigan. Production
increased year by year as new mines were added, moving
always to the west along the base of the Upper Peninsula.
In i860 the major iron ore producirg states still
were in the East, however; New England states produced
51,700 tons of ore in that year and New York, Pennsylvania,
New Jersey, and Maryland combined for another 724,500
^Minerals Yearbook, 1969, p. 453*
12Xbid., p. 451.