I would like to relaunch a subject sometimes mentioned in the past but rarely explored in depth: stone cabinet speakers. The idea came to me to talk to you about it while reading this article:
https://the-ear.net/review-hardware/fischer-and-fischer-sn70-hard-speakers/These little German speakers aren't exactly new, but they had fallen off my radar a bit. Their particularity is that their “box” is not made of MDF or Finnish birch, but of schiste (in French). Slate, if you prefer, although it's not quite the same thing. It seems that schiste has a "laminated" structure, unlike slate. I'll let the mineralogists nitpick on the subject.
Subject with which I still have a certain familiarity, since the plinth of one of my Lenco turntables is made of schiste (from the Ardennes, that's telling you...). But the material of Lencos plinths is a subject that has been debated on Lenco Heaven for a long time.
For loudspeakers, it is rarer. I'll let you appreciate the article, highlighting this passage: "
With the price of more orthodox cabinet materials such as MDF and ply rising so much recently, other materials such as concrete and slate are almost comparable in cost. Just a few decades ago, the cabinet was the cheapest part of a loudspeaker, today it is the most expensive, meaning that it is become cost effective cost effective to make a cabinet from superior materials such as carbon fiber or slate".