system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] Why didn't they toss the Horcruxes into a volcano or something?

So, it's established that Fiend's Fire is *hot enough* to destroy a Horcrux regardless of any other protections it may have.  Not *magical enough*, mind you, hot enough.  Why wouldn't that also be true of magma/lava?  

Or, since they established that there were physical means of destroying a horcrux why didn't they dump them into a vat of acid or something?  Basilisk venom isn't inherently magical, as far as I can tell it's basically just acid + poison, and it did the job fine being a purely physical substance.  

So, why didn't they think of other ways to destroy the horcrux?  I could be mistaken, if so please set me straight, but it seemed like they went through a lot of unnecessary trouble to me.
gpt
I assume it would have something to do with the Horcrux's built in defenses.  Fiendfyre is an insanely difficult and powerful magic.  Possibly hotter than lava in some cases.  Also it's magical properties and the ability for it to be controlled could have something to do with it's effectiveness. 

A Basilisk was a creature bred by dark wizards and is inherently tied to magic.  "The strength of the venom is one of the few substances known to be capable of destroying Horcruxes, causing them fatal damage that cannot be repaired."

The venom's potency is likely due to it's link with the world of magic.

Throwing a horcrux in lava would probably make the horcrux fly itself out of it, or sink down deep into it so as to prevent anyone from finding it.  A better question might be 'why didn't Voldemort just throw his horcruxs in volcanoes to protect them?"