What does this mean? Here's an example: There is no such thing as "Water" any more.
You ask: "What! What's all this bluish wet stuff then?"
You silly person, that's not water, that's 43.91 Mercury Water! I'll sell you some for 1$ per Liter.

This is however nothing NEW, since we've already dealt with this in Crops. There's never been such a thing as "Cereal", it's always been "Salt Cereal" or "Mercury Cereal" with further gradations depending on the quality. This has made the acquisition and trading of Agricultural products somewhat...complicated.
Now this applies to everything. Everything.
EVERYTHING.
ALL THE THINGS!!!
You say: "Well, DUH."
No, YOU don't understand!
Everything is now 9 Things.
9?
Yeah, there are now 9 sub-categories for every single item in the game.
Medium Salt
High Salt
Medium Mercury
High Mercury
Medium Sulfur
High Sulfur
Medium Lead
High Lead
and
Garbage
Technically speaking, we were already dealing with "Garbage-quality" goods for everything that previously had no purity, and that the variation now makes all things strictly better. This is largely true, but is offset by the purity-bottleneck caused by Compost Bins. Purity is harder to achieve than before, and so therefore matters more than before, and so the isolation of different purities is now essential.
The necessity to keep separate the different purities will create a somewhat large inventory challenge. Every item will probably be useful at some point, but not just yet, so you will need to keep more stuff around for longer in order to ensure that you will have what you need when you need it. You could always choose to ignore the new purities, and just bet that the variance in the new resources will end up slightly better than 0% purity, and in many cases you'd be right, but not all.
Back to the Water example: there are some cases where 0% pure water, however annoying it was as a purity sink, is still better than what your local water supply now gives. If you want to make Mercury Pie Dough, and your local water has only 22.31 Mercury, then that is strictly worse than Water that previously gave you a flat 25.00 across the board. You cannot just use "Water" any more, because you cannot GET "Water" because, as I mentioned at the beginning, "Water" no longer exists. If you want to make less crappy pies, you are going to need to procure a supply of Mercury-Water.
This holds true for many resources: Wrong-Purity will be worse than Generic-Purity. Getting the RIGHT purity is now the name of the game. However, Purity is tied to the land. If your land and its surroundings do not have the resources you need of the right purity, then you will have to get them from somewhere else.
How do you get stuff from elsewhere?
Trading!
Port to Boston with 24 buckets.
Post "[Jamestown] WTB Salt Boards" in the trade forum.
Form trading partnerships with neighbors who are sitting on high quality nodes!
Umm...raid neighbors for their purity supplies?
Umm...
...Who am I kidding?
EVERYBODY MAKE ALTS!!!
![Trollface ¦]](./images/smilies/troll.gif)
Wander the world with a shovel and a bucket sampling the clay and water until you find a good spot and stick your leanto there. Other humans can't be relied upon to give you what you want when you want it! Enjoy your Massively Singleplayer experience.