Green Clay

Write about a material which is extracted, mined or quarried from the ground.

Of limited use in pottery and brick making, Green Clay owes its value to its ability to detoxify Sweetroot. Despite the name it isn’t actually green, but a pale brown - it acquires the green colour on firing - though it is slow to fire and fragile. The discovery of its unique ability has made it one of the more widely traded commodities across the northern half of Marivar and turned the sweetroot from animal fodder only consumed in times of famine and failed harvests into a staple for the poor and the raw material for a range of processed products consumed by all ranks of society.

Properties

Material Characteristics

A pale brown clay of very fine grain. There is little to distinguish it by eye from other clays, though a test firing will make it clear but the development of a green colour. The ability to detoxify sweetroot is not a good diagnostic as that plant’s toxins are characterised by a slow action. Some prospectors say that it also removes the taste of naravock and they carry this herb to help identify this mineral in the field.

Physical & Chemical Properties

The mineral construction of many clays allows them to adsorb toxins. This property is especially powerful in green clay and the structural/chemical origins of this are likely to be the cause of the poor physical properties of the fired material.

Geology & Geography

It is most commonly found in the central areas of Marivar, notably in the high plateau around Mariv-thip. It is also found in the alluvial deposits down stream of the Harren Cataracts though these deposits tend to be of poor quality as they are thin bands or lenses interspersed with sand and organic material.

Life & Expiration

The properties are stable in respect of time, but are lost with firing. After use it can be regenerated by suspending it in strongly alkaline solutions (lye or stale urine for example), though in most areas, at least those close to river or canal transport or the main caravan routes, the trouble of this makes it not worthwhile as those materials are often in short supply and wanted for other purposes.

History & Usage

Everyday use

It is widely used in the areas where Sweetroot forms a significant part of the diet and is traded beyond its natural range. The detoxification process is described elsewhere, under Sweetroot. It is also used to treat some stomach disorders and food poisoning where its effectiveness is assumed to be through the same mechanism of adsorbing toxins.

Cultural Significance and Usage

Without it the widespread use of sweet root would not have been possible. As is clear from the culinary literature of the Marivan Empire, sweetroot is a key ingredient in many of the culturally “typical” dishes of the Empire and almost any meal would be significantly different had the properties of green clay not been discovered. For some examples, see the The Kitchen Book of Larch Hill, where the clayed and purified extract is referred to as sugar.

Distribution

Trade & Market

Owing to its weight it is typically traded by water but Marivan Dromemel caravans are used to move it in areas away from the canals and rivers that have no more local source. It is widely available in most market places where sweetroot is sold and the price is determined almost entirely by the costs of transport.

Law & Regulation

There have been numerous instances of other clays being passed off as green clay or inadequate regeneration over the years. The prospectors trick has come more widely into use as a quality check but sleight of hand remains a problem for the test is only are reliable as the sample tested is representative.

The Distribution of Green Clay

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The Occurrence of Green Clay

Discovery

Discovery is often attributed to the noted empiricist Hieron Nollerute , though whether he truly discovered it or recognised the utility of a peasant practice is debated by the historians of knowledge. As any cynic will tell you, that almost certainly means they don't want to admit that the peasantry got there first. As for how it was discovered, the most probable route was through having used poorly fired green clay vessels for the preparation of food and drink. But regardless of his role in the discovery of this property, it is undoubtedly to Hieron that the wider society of Marivar owes knowledge of it.

Refinement

Little refinement is needed - for the grittier grades suspending the clay and settling out the sand is useful for unless detoxifying the juice or liquid extracts of sweetroot it is difficult to remove all traces of the mineral from the processed vegetable matter. For transport the clay is often dried - though firing it destroys the activity, drying at lower temperatures has no impact if the clay is allowed to rehydrate well before use. Dried it may be compressed into bricks to aid packing in bulk. The regeneration of the clay after use is achieved by suspending the clay in a strong alkaline solution and allowing it to stand for a day or more before decanting the liquor and washing with fresh water.

Environmental Impact

As with any mineral extraction there is an impact on the environment, but with green clay this is limited to the pits formed by its extraction. These pits are typically used as fish ponds. As yet there appears to be no risk of supply of the clay becoming limited.