Hi LookingNow,
I don’t think that most people would be able to tell the difference between blended and 100% natural Talalay if the ILD was the same in a two inch topper. They may be able to tell some difference if a whole mattress used either blended or 100% natural Talalay.
Neither one will feel like memory foam. There is more about the different types and blends of latex in post #6 here and there is more about the differences between 100% natural and blended Talalay in post #2 here. In the lower ILD’s especially, the 100% natural Talalay made by Latex International is less durable (won’t last as long) as their blended Talalay while Radium has told me that their testing indicates that both would be very comparable to each other in terms of durability.
I would treat Radium and Latex International as being close equivalents although Radium has had fewer sporadic quality control issues over the last few years than Latex International.
Firmer means it compresses less when you put weight on it and would be more “supportive” but less pressure relieving. “Firmer or softer” would be more meaningful for most people than “harder or softer” when it comes to describing a mattress material. For example an innerspring is made with steel which is a “harder” material than foam (or even a wooden floor) but an innerspring may be firmer than a soft foam or softer than a very firm foam and would certainly be softer than a wooden floor even though it’s a “harder” material.
There are three different types of foam materials which are polyfoam, memory foam, or latex foam. You can find out whether a mattress or topper uses polyfoam by looking at a law label which will list the materials. The same would be true for memory foam (viscoelastic foam) or latex. Different types of polyfoam or memory foam have different chemical compositions so the testing and certification would tell you whether any chemicals or VOC’s in the polyfoam were within the limits of the testing. You can see the Certipur testing limits here* and the Oeko-Tex testing limits here (both of them have a formaldehyde VOC limit value of .1 mg/m3). PBDE’s haven’t been used in mattress materials made in North America for many years. There can be dozens of chemicals in memory foam and to a lesser degree in polyfoam so some people with MCS will often choose to avoid one or both completely rather than take the chance it will affect them although some types of memory foam or polyfoam may also be fine for you. While it’s a very complex and confusing issue and there is a lot of misinformation on both sides of the “safety” issues in the industry … post #2 here and the other posts and sources of information it links to that can help each person answer the question of “how safe is safe enough for me?” on a more individual level.
ADMIN NOTE:*Always check CertiPur site for the latest guidelines available
While there are no rules that apply to everyone and there are always exceptions … for most people with MCS any type of latex would usually be a “safe” choice but carrying a sample of a material you are considering around with you for a day or two can always be a good idea to make sure you aren’t an exception.
Phoenix