Can the decompistion of one carbonate inhibt the decomposition of another carbonate?

If two different carbonates of Group II, are mixed in equal amounts and then heated could one of the carbonates decomposition inhibt the other ones decomposition?


I don't understand how it would because (as far as I am aware) the reaction is not an equilibrium.


However I was told that if:



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> Equal masses of barium carbonate and magnesium carbonate powders are mixed together, and then heated using a Bunsen burner flame until there is no further change.
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then



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> The residue left after heating reacts with aqueous hydrochloric acid to produce carbon dioxide.
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This suggests that not all of the carbonate decomposes. However (from Wikepedia) 


* Maximum temerature of a Bunsen burner flame is 1560 degrees celcius
* Thermal decompistion of barium carbonate starts at 1360 degrees celcius
* Thermal decompistion of magnesium chloride starts at 350 degrees celcius and is considered complete above 900 degrees celcius


This suggests that all the carbonate decomposes, however I am skeptical of this (Wikapedia) data.


So is thermal decompistion being inhibted? Or is barium carbonate simply not undergoing full decompistion (Wikapedia data is wrong)?


*I couldn't find anything about it but maybe barum carbonate, like magnesium carbonate needs a much higher temperature than stated to fully decompose?*


