That seems statistically extremely unlikely, to say the least. If you don't care what card you win (i.e. try for one that you have, say, two matches of already even if you don't want it) I'm pretty sure it is over 50%, from personal experience, and probably more like 75%. If you target a specific card you need and ignore the rest, it's going to drop a fair amount, depending on what you're aiming for. Personally, I have also had problems mixing up the air and aether shards because they look so similar to my eyes, and there's been more than a few times where I've found myself staring at what I thought was a match of 3 but was actually a mix of the two shards upon closer inspection.