Calcium hydroxide can be made by mixing a soluble calcium salt with sodium hydroxide, all in solution of course. Calcium hydroxide made in this manner will be somewhat difficult to separate from any excess of sodium hydroxide, however.
Another option is roasting calcium carbonate at 1100°C or greater. This produces calcium oxide, to which you can
cautiously add water to make the hydroxide.
WillieTheDude wrote:I have found this acid to be required in number of tekks and this is simply non existent when I google search in my language.
What language? Fumaric acid is a trivial name for
E-butenedioic acid and as such may have an entirely different name in your language.
Related example: Succinic acid is the trivial name for butanedioic acid (yes, butane-, not butene-), which in German is known as "Bernsteinsäure" (translating literally as "amber acid"

- although fumaric acid is simply "Fumarsäure".
Fumaric acid can be obtained from natural sources - particularly
Fumaria officinalis, which contains (relatively) large amounts of this substance.
“There is a way of manipulating matter and energy so as to produce what modern scientists call 'a field of force'. The field acts on the observer and puts him in a privileged position vis-à-vis the universe. From this position he has access to the realities which are ordinarily hidden from us by time and space, matter and energy. This is what we call the Great Work."
― Jacques Bergier, quoting Fulcanelli