I guess there isnt any, but in my experience, there is no noticable difference from different blends of changa and pure DMT, atleast not to me, unless there is salvia divinorum in the changa, which there often is, people cut their changa with salvia and pass it off as the real thing, atleast here in scandinavia, when i get that type of blend there is a major difference, but from one herbal mix to another its more or less the same, to the degree dmt trips can be the same
Copper has been used and cherished for around 9,000 years. Pots that are made of copper are ideal heat conductors; the material is durable, hygienic and corrosion-resistant. Above all, it is the excellent heat conductivity that makes copper a perfect base material for pots and pans.
When copper is oxidized by a combination of air, humid and finely divided acid and salts in the air, then a so-called patina of copper is formed. This is a basic copper (II) carbonate/sulfate mix, which has a cyan color. The reason that the color changes is that a chemical compound of copper is formed. Copper itself is a metallic element. Compounds of elements can have totally different properties than the elements themselves (e.g. look at hydrogen and oxygen, these are gasses at room temperature, while the compound water, made of both elements is a liquid at room temperature). A similar thing you see with iron.