What I know about 'made from' and 'made of' is this:

Chairs are made of wood - the wood is still wood, you see that AND
Paper is made from wood -wood disappears, you don't see wood

What I know about the word virgin as an adjective is this:

in its original pure or natural condition and not changed, touched or spoiled

So, keeping in mind that if *the original material is changed, it does not remain virgin. Said that, --[anything] made FROM virgin [anything] is not possible.

But here...

What makes it (they are talking about 3D printer filament) especially attractive is the cost of conventional filament made from virgin plastic: about $35 to $50 a kilogram.

The Guardian reads:

Extra-soft, quilted and multi-ply toilet roll made from virgin wood causes more damage than gas-guzzlers, fast food or McMansions, say campaigners

Question

Now, if we change/alter the original material, how is it possible to call it virgin? The moment you change/alter the main material, it's not virgin anymore! :)

So shouldn't we use 'made of virgin' (since it's not changed) over 'made from virgin' which means 'altered'.