Transferring the method to ceramics has brought additional challenges but initial results have demonstrated that ceramics have the same “internal clock” as bricks. These studies have encountered issues with components within the ceramics causing either addition mass gain or additional mass loss during the RHX measurement process.

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According to the RHX power-law, if the weight of a fired-clay ceramic increases as a result of RHX by 0.1% in 1 yr from firing, then the weight increase is 0.2% in 16 yr, 0.3% in 81 yr and 0.4% in 256 yr (and so on).

The RHX method depends on the validity of this law for describing long-term RHX weight gain on archaeological timescales.

For example, a medieval brick examined by Wilson and collaborators The main application of the RHX technique is to date archaeological ceramics.

Yet most archaeological material contains components which causes either addition mass gain or additional mass loss during the RHX measurement process.

There is now strong support for power-law behaviour from analyses of long-term moisture expansion data in brick ceramic, some of which now extends over more than 60 y.

Moisture expansion and weight gain are known to be proportional to each other for a specified material at any specified firing temperature.A small piece of the ceramic is first removed, weighed, and heated to 500 °C, effectively dehydrating it completely.The amount of water lost in the dehydration process (and thus the amount of water gained since the ceramic was created) is measured with a microbalance.Starting in 1842, England has offered registration of it's decorative designs for pottery, china, wood, paper, pottery, china, porcelain, glass and more.By using the information below you can find the date a design was registered. Remember this date is just when the design was registered.This reaction reincorporates hydroxyl (OH) groups into the ceramic material, and is described as rehydroxylation (RHX).