Hello, I recently begun experimenting with alkali based binders for art projects.

I made this samples using clay from digging up to the stagnogley layer in my garden. Left one has sand aggregate and was steel brushed, right is binder paste only and was wet polished on a 300 grit diamond plate.

I'm not concerned with the structural properties of the results, rather colour and appearance. I've been using clay, silica gel, sodium silicate, lime, wood ashes and sodium hydroxide to make a cement paste that I mix with sands.

I've been working on eyeballing proportions, making mixes without any measurement other than 'scoops' with varying degrees of succes. From mixes that never set, mixes that set with high content of unreacted clay, good mixes that set very hard and take polish, and mixes that dry and crumble to hand pressure.

To make the cement: 1 - I mix clay with sodium meta-silicate, silica gel and a diluted sodium hydroxide solution to make a 'soup'. I Stir once a day for at least 1 week. It keeps at about 25 degrees. It starts lumpy and by the end of the week, (bit longer in winter) it has the consistency of slaked lime and will quickly sit at the bottom of the bucket if stirred. If the silica gel doesn't fully dissolve in the first few days I add more sodium hydroxide until it does.

2 - I mix lime, wood ashes, more clay and hydrate on a conventrated sodium hydroxide solution, quickly and using protection because this step is evil. The vapours are irritating while mixing, any splash of the mix burns skin. (I'll need to add lime differently because this is very difficult to mix)

3 - Mix vigorously 1 and 2. This step is also hard because the mix of 2 is a clay ball that takes a lot of stirring until it all becomes a paste with 1.

4 - mix the paste with aggregate sand and cast!

Thought of sharing here, thought the sub looks dead. Appreciate any feedback in the process as I'm sure there much are better ways to do this!

I'd like to find out if there's any fresh information on murrhine, that artisanal material described by Pliny the Elder as a thermosetting liquid that was formed into highly prized tableware. I first read of it in Dr. Davidovits's book "The Pyramids" back in 1988.

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There seem to be quite a few "murrhine" pieces on display in museums that are nothing more than carved fluorite, neither all that precious nor anywhere near durable enough (at a Mohs hardness of 4) for such applications. Since Elagabalus was said to have collected murrhines, that would place an active knowledge of that technology as recently as the third century CE.

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Are we just seeing endlessly recycled and garbled accounts of something that's not particularly remarkable (carved semiprecious stone or ceramic) or is there something more to it?

At this point, I believe there is sufficient evidence to confirm that the ancients were using geopolymers in the construction of certain megalithic sites. Two of the most damning pieces of evidence/phenomena are:

1. Air bubbles found in limestone blocks (impossible to get there without modifying the properties of the stone)

*( X-Rays Analysis and X-Rays Diffraction of casing stones from the pyramids of Egypt, and the limestone of the associated quarries., Davidovits J., Science in Egyptology; A.R. David ed.; 1986; Proceedings of the “Science in Egyptology Symposia”; Manchester University Press, UK; pp.511- 520.)

and

2. Stones found with intentionally altered densities. There are many pillars in Indian temples that have been "tuned" to resonate at a particular pitch when physically struck. This can only be possible by altering the density of the stones.

With this new perspective, the question isn't so much "did they use geopolymers?" The answer is yes. The better question is "how did they make the geopolymers?"

I don't think we'll find the full answer in a combination of acids and chemicals, though I don't entirely discount their use.

My main theory revolves around using electromagnetic fields to soften these stones. There is a clear relationship between resonant frequency and material removal rate. The closer you are to resonance, the faster the material is removed. This rule of thumb holds.

Now consider this: Electrochemical or Discharge Machining both use electricity in their respective processes. All that would be necessary for EDM to be applied to stone is for the stone to be electrically conductive. Then, we could effortlessly achieve high precision cutting in stone.

On paper, if we could figure out how to make stone blocks sufficiently electrically conductive, these machining techniques would work with little to no adjustment in methodology.

However, if the solution does not lie in making the stones conductive and then using a discharge-machining technique, it probably lies in altering their innate electromagnetic properties.

In the case of these non-conventional machining methods, the piece to be cut is an anode, while the cutting tool is a cathode. We usually think of "cathode" and "anode" in the context of a battery, but cathode and anode are relative terms, meaning technically that when you throw a slice of pizza in the microwave, the pizza and interior of the microwave oven are anodes, and the magnetron is a cathode. Anodes and cathodes effectively describe capacitance, whether charging or discharging. These terms are relative. In a cathode ray beam, the emitter is a cathode, and the anode is the target of the beam.

Now imagine a device similar to a magnetron or cathode ray tube - that can produce an electromagnetic field sufficient to resonate the stones at the atomic scale. The frequency range would likely be very high, probably 200+Mhz, if not higher. This would replicate the electrical conditions that originally formed the stone, just without the heat and pressure. By exposing a rock to this electromagnetic field, it would become like clay, getting softer and more workable.

As a secondary effect, the exposure of the stone and surrounding land to this unique electromagnetic field may influence the gravitational behavior of the stones. Specifically, if the ground is negatively charged, and so is a cut stone from a quarry, the charges should oppose, which would effectively lift the stone from the ground. In this case, the capacitance of the ground and the stone would be of the same potential, so they would oppose each other by physically separating, increasing the amount of space between them.

Basically, the theoretical device puts a charge in the ground as well as the stone being worked on, and this likeness of charges causes the stone to rise proportional to the strength of the applied field.

The specifics on this theory are a bit sparce, but I think it has good merit in principle.

Let me know what y'all think.

Would this process result in the formation of a true geopolymer (actual polymer molecular networking): baking and then crushing kaolinitic clay, mixing it thoroughly with slaked lime, let reaction occur and then add crushed limestone, sand, and more kaolinitic clay, mix, then let set in the sun, cure with salt water
?

does any part of this process not make sense, and if so why?
My understanding is that to achieve true geopolymerization it is necessary to first depolymerize the naturally occurring aluminosilicates (using an alkali or acid) into a gel of "oligo-sialates" and then the geopolymerization is in two parts which is the molecular condensation and then networking to form a mineral polymer. I'm not very clear on the geopolymerization part, is there anything additional that needs to be done or is it just a matter of the right compounds present to react in this way automatically after mixing of the oligo-sialates stops?

I have been watching Joseph Davidovits' videos on the Geopolymer Institute youtube channel, and reading other things I can find but I still haven't found a clear detailed description of what must be done specifically to achieve true geopolymerization.

For context, I am trying to create geopolymer concretes from only local materials, without the use of laboratory equipment, so.. not using fly ash or blast furnace slag and mixing everything outdoors with hand tools. kaolinitic clay (Pennsylvanian Underclay), limestone, and salt can be found locally in my area. I've also considered adding hardwood bark ash and dolomite but I am not clear enough on the chemistry to know if this would be beneficial or detrimental to the end result.

Thanks for reading

Would it be possible to build a swimming pool slab using fly ash and slag geopolymer? I think this is called Alkali-activated fly ash-slag (AAFS).

Are there risks to doing this? I mean like heavy metals leaching out from the geopolymer slab into the water?

Hey there I am currently conducting a project on geopolymer concrete and aggregates, is possible to make a geopolymer concrete at home, what materials and ratios are required to make the most dense and structural rigid concrete. Any help would be greatly appreciated, currently in Australia so we haven’t really moved towards a greener future just yet.

Heat conduction? Sound? Electrical?