Hi Mick04u,
100% natural Talalay means that there is no synthetic rubber in the blend at all although it doesn’t mean that 100% of the finished core is rubber because there are also additional substances needed to foam, manufacture, and cure the foamed latex core (see the first part of post #7 here).
There are only two sources of 100% natural Talalay in the western world which is Talalay Global (formerly Latex International) and Radium. A phone call to each of the manufacturers that you are considering would normally be the best source for this type of information about their current options because manufacturers can change their suppliers from time to time.
Having said that …
I believe that their 100% natural talalay comes from Radium
They use 100% natural continuous pour Dunlop made by Mountaintop Foam … not Talalay.
I believe that their current default would be Radium but they also have access to Talalay Global latex so you would need to confirm which one they are using in any specific mattress.
I believe that their current Talalay supplier is Radium.
They can provide either Radium or Talalay Global on request but they will tell you which one is their current default.
Phoenix