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cementation and process
By the Roman period brass was being deliberately produced from metallic copper and zinc minerals using the cementation process and variations on this method continued until the mid 19th century.
Brass was produced by the cementation process where copper and zinc ore are heated together until zinc vapor is produced which reacts with the copper.
There is good archaeological evidence for this process and crucibles used to produce brass by cementation have been found on Roman period sites including Xanten and Nidda in Germany, Lyon in France and at a number of sites in Britain.
16th century technical writers such as Biringuccio, Ercker and Agricola described a variety of cementation brass making techniques and came closer to understanding the true nature of the process noting that copper became heavier as it changed to brass and that it became more golden as additional calamine was added.
However the cementation process was not abandoned and as late as the early 19th century there are descriptions of solid state cementation in a domed furnace at around 900 – 950 ° C and lasting up to 10 hours.
The raw material for this was blister steel, made by the cementation process.
The manufacturing process, called cementation process, consisted of heating bars of wrought iron together with charcoal for periods of up to a week in a long stone box.
Precipitating minerals reduce the pore space in a rock, a process called cementation.
The final recovery step may involve precipitation, cementation, or an electrometallurgical process.
Essentially, lithification is a process of porosity destruction through compaction and cementation.
During the Roman period a new process of metalworking started, cementation, used in the production of brass.
There are examples of larger vessels such as cooking pots and amphorae being used for cementation to process larger amounts of brass ; since the reaction takes place at low temperatures lower fired ceramics could be used.
The cementation process, which was lost from the end of the Roman to the early Medieval period, continued in the same way with brass.
Furthermore, the process for carrying out cementation for brass did not change greatly until the 19th century.
However, during this period a vast and highly important technological innovation happened using the cementation process, the production of steel.
The technique was the cementation process.
The Bessemer process and more modern methods differ from crucible steel production in that they remove carbon from the pig iron, but stop before all the carbon is removed, whereas the ultimate raw material for traditional crucible steel was wrought iron, to which carbon had been added by cementation.
Besides supplying Williams with large quantities of plate and equipment Wilkinson also supplied scrap for the process of recovery of copper from solution by cementation.
He also acquired an interest in the patent for the cementation process of making steel in about 1615.
The cementation process is an obsolete technique for making steel by carburization of iron.
In the early modern period, brass, an alloy of copper and zinc, was usually produced by a cementation process in which metallic copper was heated with calamine, a zinc ore. For details of this see calamine brass.

cementation and continued
However Champion continued to use the cheaper calamine cementation method to produce lower zinc brass and the archaeological remains of bee-hive shaped cementation furnaces have been identified at his works at Warmley.

cementation and be
Fortunately, the degree of cementation in Portland Stone is such that the stone is sufficiently well cemented to allow it to resist weathering but not so well cemented that it can't be readily worked ( cut and carved ) by masons, this is one of the reasons why Portland Stone is so favoured as a monumental and architectural stone.
This can then be sent to the lab where the two pieces will be soldered and returned for another try-in or final cementation.
* A cementation furnace might be used to convert the bar iron ( if it was pure enough ) into blister steel by the cementation process, either as an end in itself or as the raw material for crucible steel.

cementation and used
Islamic cementation seems to have used zinc oxide known as tutiya or tutty rather than zinc ores for brass making resulting in a metal with lower iron impurities.
" This local zinc was used in speltering and allowed greater control over the zinc content of brass and the production of high zinc copper alloys which would have been difficult or impossible to produce using cementation, for use in expensive objects such as scientific instruments, clocks, brass buttons and costume jewellery.
The term diagenesis is used to describe all the chemical, physical, and biological changes, including cementation, undergone by a sediment after its initial deposition, exclusive of surface weathering.
These crucibles are used in the same way as other cementation vessels but with a hole in the top of the vessel to allow pressure to escape.

cementation and from
Zinc metal was also becoming more commonplace By 1513 metallic zinc ingots from India and China were arriving in London and pellets of zinc condensed in furnace flues at the Rammelsberg in Germany were exploited for cementation brass making from around 1550.
Stromatolites or stromatoliths (; from Greek στρώμα, strōma, mattress, bed, stratum, and λίθος, lithos, rock ) are layered accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains by biofilms of microorganisms, especially cyanobacteria ( commonly known as blue-green algae ).
The first examples of cementation steel is wootz steel from India ( Craddock 1995: p276 ), where the crucibles were filled with the good quality wrought iron and carbon in the form of organics such as leaves, wood etc.
Curtis, and J. Esson, 1995, Complex cementation textures and authigenic mineral assemblages in Recent concretions from the Lincolnshire Wash ( east coast, UK ) driven by Fe ( 0 ) Fe ( II ) oxidation: Journal of the Geological Society, London, v. 152, pp. 157 – 171.
The radiocarbon dates from the cement demonstrate that the beachrock composing the Bimini Road formed about 2, 800 radiocarbon years ago by the cementation of pre-existing sediments that accumulated about 1, 300 years earlier.
The degree of cementation varies from being relatively weak within the interior of a boulder to quite hard within its outside rim.
The Moeraki Boulders are concretions created by the cementation of the Paleocene mudstone of the Moeraki Formation, from which they have been exhumed by coastal erosion.
Various techniques have been practised ; salt cementation from ancient times, parting using distilled mineral acids from medieval times, and in modern times using chlorination using the Miller process and electrolysis using the Wohlwill process.
Differential cementation and later erosion of cross-bedding inherited from the riverine sand, in which these concretions occur, created the " ornamentation ", which these concretions exhibit.

cementation and which
The compositions of these early " brass " objects are very variable and most have zinc contents of between 5 % and 15 % wt which is lower than in brass produced by cementation.
In case of pervasive growth, cementation of the host sediments, by infilling of its pore space by precipitated minerals, occurs simultaneously throughout the volume of the area, which in time becomes a concretion.
The resistance of the cohesionless soil to liquefaction will depend on the density of the soil, confining stresses, soil structure ( fabric, age and cementation ), the magnitude and duration of the cyclic loading, and the extent to which shear stress reversal occurs.
Brooke's furnaces were probably in his manor of Madeley at Coalbrookdale ( which certainly existed before the English Civil War ) where two cementation furnaces have been excavated.

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