CO129-553-8 Tin- analyses of assay 11-3-1935 - 4-3-1936 — Page 30

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method used by Messrs. Griffith is, however, somewhat neater than

that used in Hong Kong and I am considering the question of changing

over to their method on my return. If the sample assays 99% or over

of tin, a certificate is issued to the exporter to this effect. The

exporter receives up to 6 certificates of assay and can on payment of

$2 for 3 copies, be supplied with as many more as he demands. If the

assay figure falls below 99%, the Hong Kong laboratory mark is

cancelled on the slabs, which are re-refined, sampled and assayed again.

In many cases, when the tin is sampled, no shipping marks

are present on the slabs. These marks of identification, name of

ship on which the tin is to be despatched and destination, are put

on the Laboratory certificate from information supplied by the

exporter and it is definitely stated on the certificate that this

Very often, the parcel

information is supplied by the exporter.

of tin shipped

say of 2000 slabs is landed in 400 slab lots at

various ports on the journey.

LONDON.

-

On arrival of a parcel of tin here, it is weighed out

in 10 cwt. lots (drafts). Until after my visit to the Docks, one

slab, irrespective of the size of the slabs, was taken from each

draft by the wharfingers and sampled by sawing, no representative of

the importer being present. Each 10 drafts, i.e. 5 tons, is sold

under a warrant number and in the case of Chinese tin, not more than

5 warrants, i.e. 25 tons, can be assayed as one lot. The sawings

are collected and divided into three by the wharfingers.

One sample

is sent to each of two assayers for assay. If they do not agree, a

third sample is sent to a third assayer, whose report is final and

binding.

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