I live in “No Latex Mattress Land” i.e. a 12 hour highway drive to the nearest store, so online is my only option. Mattress Underground has been great at educating me and helping me find reputable online dealers. I live on the east coast of Canada so it boiled down to 3 stores. BUT…
Spindle mattress has a Firm 3" continuous pour natural Dunlop at 98kg/m3 (Neil said) with an ILD of 29.5-32.5.
MemoryFoamComfort has a blended Talalay 6" core with an ILD of 49 but Mario’s email states that the Talalay density is 3-3.5lbs/ft3.
These numbers are in total disagreement from Phoenix’s Apr 25, 2013 post. Does someone have an explanation?
Spindle mattress uses a continuous pour 100% natural Dunlop which will have a different density for each ILD than either blended or natural Talalay. The ILD’s or densities of different types of latex won’t match with other types and blends of latex (see post #6 here). ILD is also only one part of the factors involved in how soft a layer or a mattress will feel (see post #4 here).
Comparing the ILD’s or densities of different types and blends of latex is an “apples to oranges” comparison and I would go by your discussions with each manufacturer rather than trying to make ILD comparisons that aren’t really possible or relevant between different types of latex. The post you linked has density and ILD information about 100% natural Dunlop that is manufactured in a mold and about blended Talalay and wouldn’t be relevant to other types or blends of latex or latex layers that used a different method to test ILD.
When you are working with an online manufacturer and you can’t test a mattress in person for PPP then I would pay much less attention to “comfort specs” such as ILD and much more to the knowledge and experience of the manufacturer that is specific to their mattresses because they are in the best position to help “talk you through” the options they have that have the best chance of success for you and will know more about matching their own mattresses to different body types and sleeping positions than anyone else or any type of “theory” based on a single spec such as ILD that will only tell you a small piece of a much larger picture (see mattress firmness/comfort levels in post #2 here).