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 Mr. Gowland in his very satisfactory report (l.c,. [sic]) of this year, states, that as a rule Japanese copper is exceedingly free from the presence of injurious metals. Out of thirty-eight analyses of different samples of Japanese copper he made the following summary: “Sulphur, silver, lead and iron were present in small and varying proportions, in every case; in one specimen however an abnormal quantity of lead existed. The whole of the samples were remarkably free from the specially injurious metals, antimony and arsenic; antimony being present in only one specimen, and then only in faint traces, while the maximum amount of arsenic only reached 0.057 %, and in 31 cases it was either absent altogether, or the merest traces only were found.”

In the rectangular cake copper (dry copper, ma-buki-do), Mr. Gowland found, as we did, an excess of cuprous oxide.

We only analysed three different kinds of bar-copper, and found in each of them traces of arsenic, besides some sulphur and iron.

The average composition of Japanese crude copper, made up out of the numerous analyses by Mr. Gowland (l. c.), may be stated as follows:

We must advise the commercial community to make a careful distinction between the different kinds of Japanese copper, there being some of a very impure character, as for instance the copper plate-roofs of Japanese temples, which are very impure and mixed with lead. Bar-copper (Saö-buki-do) is the purest of all Japanese coppers.

The Portuguese from 1550-1639 exported chiefly gold