archaeometallurgy

Another superlative from in Pločnik in Serbia: This time the team of the Rise of Metallurgy project has found evidence for the earliest known tin-bronze. The recovered artefact, a thin sheet bronze fragment, is at least 6500 years old and consists of a copper-tin alloy with 11 wt% tin, and a number of minor elements . Archaeologists call copper alloys with zinc brass, all others are often labelled as bronze. In order to clarify that it is bronze in the sense of the modern definition, in archaeological texts it is often referred to  as tin-bronze. Alloys with arsenic are called in the rest of the best arsenical copper. Continue reading

Gossan is a term from mineral economics. The gossan may also be called iron cap. This is so because it denotes a concretion of iron hydroxides that has formed on top of sulphide mineral vein, where it reaches the surface. It forms during the supergene sulphide ore enrichment, when weakly acid surface water perloctaes through the mineral deposit. Many sulphide ores are oxidised in this process and brought into solution:

Schematic view of a sulphide vein. You can see the oxidation zone, consisting of the gossan, the leached zone and the oxidised zone. The reducing zone consists of the enrichment zone and the area of ​​primary mineralization. Significantly modified after Evans (1992) and Ottaway (1994).

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This article is about managing your micrograph collection without the need of a dedicated data base structure. You can keep your filing structure and will not be dependent on a proprietary management system. The article is centred around embedding meta information within the digital image. Micrograph, microscopical observations and related notes are always kept together. Because of the standardised way meta data is stored in digital image files, it may be easily exported.

Ddigikam enables you to save your microscopical observation notes directly into the meatadata of your micrographs.

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