Ores

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In (Bulk)vessels Ore shipments are transported from mines to the loading vessel by various means, including rail, road transport or by craft, and a certain loss may occur during transit and during loading operations.
In many cases the weight of the cargo loaded is measured by taking the draught of the vessel, but the weight so ascertained is not absolutely reliable. In calm weather and under normal conditions measurements so ascertained are recognized as being generally reliable. Shipped weights are sometimes provided by vehicles passing over a weigh-bridge, prior to shipment, but such weights are not necessarily evidence of the quantity loaded, by reason of the margin of error which must be allowed and the loss which may take place during the actual loading operations, particularly if the ore is dry and dusty. Similarly, methods of determining the arrived weight at the port of discharge vary and are subject to the same considerations.
The weight at destination may also vary due to the drying out of the natural water content during transit and loss due to such cause may differ considerably, as in wet weather the ore is likely to contain an excess over and above its natural moisture content. It is usual for the moisture content of the ore to be determined at the time of shipment by a chemical analysis of samples drawn during loading, and it is customary for the ore to be bought on the calculated dry weight.
Ores of various types should in general be kept separate, the mixing of one with another being likely to result in an appreciable claim. This is of particular importance where, arising out of a casualty, cargo has to be discharged at a port of refuge and interim storage facilities are limited.
Ores are often carried by ships as concentrates which may liquefy and which may present self-heating properties in bulk (e.g., metal sulphides concentrates).
Must be kept separated from other cargoes to avoid damage from sifting, moisture or contamination.

In container(s) Bulk ores in dry and fine-grained condition may have shifting characteristics similar to grain. Depending on the variety of ores in purified or washed (gritty) condition, the collective name "Concentrates" has to be marked on the container.
Mixing of concentrates and ores has at all times to be avoided even when both are of the same type, e.g. chrome ore and chrome concentrate. Stowing two types of bulk ore in the same container is not allowed as contamination may lead to considerable claims. Chrome ore affects other commodities and similarly it should be protected from contamination by other cargoes.