Yes. Natural rubber yoga mats naturally give off a rubber smell. One brand's mat may smell a little different than another's, but they all have that smell as a by-product of the material itself.
Will that smell go away? Yes.
How long will it take? That varies. Generally, from a couple of weeks to a couple of months. Part of this depends on how you clean it and care for it, part of it depends on how sensitive you are, and part of it is due to the fact that natural rubber has varying degrees of odor.
Tips to Getting Rid of that Rubber Smell in your Yoga Mat:
Air out your new mat in a well-ventilated area - maybe even use a fan, or open a window while draping it over something
DO NOT air out your natural rubber mat in direct sunlight due to it's photo-sensitivity
Keep it unrolled often. The tighter it is rolled and the more it is left enclosed in your yoga mat, the longer the smell will hold
Clean your mat often in those first few weeks. Use a mild soap on a rag and rub it down, then with a wet rag rinse it off well. Clean both sides and hang dry.
Manduka recommends wiping their natural rubber mats with a solution of 50/50 organic cider vinegar and water or Manduka’s Mat Restore (a vinegar based solution)
Note: It is important to note that the smell is natural and not a result of off-gassing from toxic chemicals.
Tips for Washing your Natural Rubber Yoga Mat:
Jade Yoga's mats act like sponges and hold water. If soaking, allow enough time to rinse and dry thoroughly
Jade Yoga says: If you choose to use a washing machine, only wash in a front loading machine (no agitator) and only use gentle
Manduka says: DO NOT put the eKO mat in the washing machine as it will encourage the material to biodegrade
DO NOT dry or expose your mat to excessive sunlight