Yoga blocks are truly a staple in my practice, allowing me to benefit from the postures instead of simply trying to keep my balance! (or hurting myself... and pulling my achilles tendon was not fun!). I bought my first yoga block about the same time I started to be able to touch my toes.
Typical yoga blocks are made with foam filled with phtalates, PVC and whatever else ridiculous toxic chemicals. These foam blocks are not eco-friendly, are difficult to recycle and will clog-up the landfills (think of all the yoga blocks at the yoga studio you attend! More on ecofied studios later though).
During my research for this post I've found mention of some foam "eco" alternatives at "Barefoot Yoga Co." among others. Although they claim that the process is "green" it's only vaguely described and there are no third party eco-certifications to back their green production claims.
The other two options that I think are fantastic are: Bamboo and Cork.
1. The Cork Yoga Block
You can find these blocks at Gaiam and Manduka to name two. Cork is harvested from the bark without any real harm to the tree. They have documented that the Cork tree's process of regrowing the bark actually consumes much more CO2, which is fantastic for the environment! Cork is also a very cushion-y and springy substance that has a lot of give. So for those Yogini/Yogis that love the softness of foam; Cork might be a nice alternative for you! The cons: I really couldn't find any info on how the cork was bound together to make the block- is there glue or a chemical process involved? Also, a cork block will not last as long as say... bamboo!
2. The Bamboo Yoga Block (my choice!)
My block actually came from Lulu (shame!! I know... haha), but you can buy bamboo blocks from most yoga companies. Bamboo is a sustainable, extremely durable grass that also needs a lot more CO2 to grow than trees! It's strength and durability will assure a lifetime of use and it's super lightweight! The only negative aspect of bamboo is the current debate regarding harvesting methods. Due to the rise in demand for bamboo, less than palatable methods (including ridiculous amounts of pesticides, desecrating rain forests, taking over local crops and slave labour) are being used to make our props so we can achieve our "zen". Sadly, how the block was harvested is still difficult to know.
I LOVE my block and have been considering getting another for friends and the Fiancé (I really don't want to share, but if I am the anti-gumby then he's.... um maybe like a strong branch...).