In the last year or so, I have noticed the arrival of corks that are very resistant to deformation and which have a very uniform, smooth, light coloured surface. One was in fact so smooth and solid that I thought at first it was plastic.
I have just broken a couple apart, which required a monkey wrench and a pair of pliers - no chance of doing it with my bare hands. The inside is a lot darker, possibly a bit darker than most corks, but more normal looking. On the edge of the broken surface you can see that the lighter colour has penetrated the cork a little, or perhaps it is a coating with a thickness you can just about make out with the naked eye.
Anyone know how these corks are treated, and why? With some plastic corks looking a lot more like the real thing (TWS example: Ca’ dei Frati Lugana) it is getting quite confusing.
An example of a hard light coloured cork from TWS is that in Aranleón Sólo Bobal, Utiel Requena 2016.