Nice, thanks Don't go to further trouble, I doubt I need more than general lines.
I may be back further, as I have some pottery thoughts, but those might not require detailing yet/at all. [I think patterned or speckled bricks look better too] The note of centrally placed bricks being better than those about the edge of the kiln I'd heard before, in reference to tile making. I read of kilns of tiles being laid out at the edges then the more expensive edging and detail tiles placed in the middle. I guess that that might be why. Ta Sue McE > Manganese or Cobalt will work for black. > Heavy amounts of Cobalt give a very black colour with overtones of blue in > a firing... again oxidation firing. > > I can look up reduction firing (which are more normative for brick) > colours once I am home this evening. > > Reduction firings tend to give either more earthy tones or in some cases > more metalic tones. > According to my pottery instructor (who's done a fair amount of reduction > work) > > more then 2% iron oxides in reduction fired bricks will make them very > brittle. > Copper in reduction fires is red or red violet > Iron tends to be black or a greeny black colour - responsible for the > colour in Celadon glazes. > Green in reduction fires is very very uncommon - requires high amounts of > barium > Manganese is brown > Cobalt is blue - violet > Copper and cobalt mixed gives wine red to a red hued purple > > My experience with reduction fires (which is admitably limited, and all > were done using pre-industrial techniques) is that the colouring is never > entirely uniform. Flashing occurs with pit fires (which are vaguely like > firing a brick works but different). Since you don't have uniform heating > in either of these types of firings you get some spots in the pile of > bricks (or pottery) that are at different temperatures or have more or > less oxygen getting to them; so the results are highly erratic (and IMO > more interesting). > > Modern methods have strived to make these things much more uniform - and > have for the most part succeeded... which means more stable bricks - but > colour wise also more uniform. > > For those who have never seen brick fired - in pre-industrial times folks > basically make a bunch of bricks stack them in large pile with holes at > the bottom to put fuel... I think of it as building the bricks around a > fuel pile. Then light the works - the pile of bricks you are firing act as > both kiln and object being fired. The most uniform (and traditionally the > most expensive) brick would have been those that were in the center of the > pile of bricks. > > So more expensive brick is both more stable (ie doesn't break or crumble > easily) and more uniform in look. Which if you are running a campaign that > could be a subtle hint about the relative wealth of the person who made > the building or wall. > > -Sue > > --- On Tue, 11/2/10, Nigel McCarty-Eigenmann > <[email protected]> wrote: > > > From: Nigel McCarty-Eigenmann <[email protected]> > > Subject: RE: [gurps] A question about Bricks > > To: "'The GURPSnet mailing list'" <[email protected]> > > Received: Tuesday, November 2, 2010, 11:35 AM > > What I am looking for is some > > regional definition for some cities in a > > fantasy setting I am currently hammering into shape. > > > > My base city for the setting has brick yards out side of > > its walls, where > > they raised the battalions of infantry and the starting > > seeds for > > republicanism came about > > > > The sign of four bricks is the ministerial sigil that looks > > after bricks, > > the building industry, and the army. > > > > Since the region is known to have iron bearing sands, so I > > am mooting Red > > Brick for the city, but I would like to have black, as > > black would suit the > > religious iconography I have got up and running. > > > > ... I could handwave a bit and say its manganese oxide and > > call the bricks > > black even though they are actually dark brown? That > > also allows the > > Damascus steel from the uplands tribes I wanted... > > > > [Green Brick is for the Lakeland towns where good brasses > > are made, and > > copper and tin mines abound] > > > > ...so Ta Sue :) > > > > McE > > > > > -----Original Message----- > > > From: [email protected] > > [mailto:gurpsnet-l- > > > [email protected]] > > On Behalf Of Susan Koziel > > > Sent: 02 November 2010 16:46 > > > To: The GURPSnet mailing list > > > Subject: Re: [gurps] A question about Bricks > > > > > > Not brick making but pottery/glazing... which has some > > of the same colour > > > effects (depending on if the bricks are fired under > > oxidizing or reducing > > > conditions... the colours I'm listing are for > > oxidizing conditions. I am > > > not sure of reducing condition colours - I do not do > > enough reduction > > > firings to know what colours the various oxides give. > > > > > > Cobat oxide - blue > > > Iron oxide - red > > > Copper oxide - green > > > Manganese oxide - brown > > > > > > Granted these colours are based on the fact that the > > clay body you are > > > using for the bricks is white or grey and not black or > > red. > > > Red and some of the black clays fire to a red colour > > so mixing oxides with > > > them just tends to give muddy versions of the colour > > of the oxides. > > > > > > Different combinations of minerals will give you > > different colours due to > > > chemical reactions... so it doesn't work like a > > painting where you can mix > > > colours - sure you can mix the colours but blue > > (cobalt) and red (iron) do > > > not give purple... it acutally gives a sort of goldish > > colour or a muddy > > > brown - depending on proportions of the mix. > > > > > > Often time the colour of bricks has to do with the > > local clay they made > > > the brick from - typically brick is made from the > > cheapest local clay > > > deposit. So the colour is more a consequence of which > > of the brick works > > > you get the brick from. > > > > > > The exception to this is the brick that is made into > > high temperature > > > brick - where they take high quality clays and have > > specific recipes that > > > allow the brick to survive high temps or exotic > > chemical conditions. > > > Fire brick is pretty much a uniform yellow/beige > > colour. > > > > > > -Sue > > > > > > --- On Tue, 11/2/10, nigel mccarty-eigenmann > <[email protected]> > > > wrote: > > > > > > > From: nigel mccarty-eigenmann <[email protected]> > > > > Subject: [gurps] A question about Bricks > > > > To: "Gurps" <[email protected]> > > > > Received: Tuesday, November 2, 2010, 6:22 AM > > > > Dear Groupmind, > > > > > > > > Anyone know about brickmaking? > > > > > > > > What mineral contents would make a brick come out > > of the > > > > oven blue, green > > > > and black? > > > > > > > > > > > > McE > > > > > > > > > > > > _______________________________________________ > > > > GurpsNet-L mailing list <[email protected]> > > > > http://mail.sjgames.com/mailman/listinfo/gurpsnet-l > > > > > > > _______________________________________________ > > > GurpsNet-L mailing list <[email protected]> > > > http://mail.sjgames.com/mailman/listinfo/gurpsnet-l > > > > _______________________________________________ > > GurpsNet-L mailing list <[email protected]> > > http://mail.sjgames.com/mailman/listinfo/gurpsnet-l > > > _______________________________________________ > GurpsNet-L mailing list <[email protected]> > http://mail.sjgames.com/mailman/listinfo/gurpsnet-l _______________________________________________ GurpsNet-L mailing list <[email protected]> http://mail.sjgames.com/mailman/listinfo/gurpsnet-l
