ketamine cutting agents? Analog?

What is the most usual cutting agent,i got some shards, ie rectangular crystals, but i think it is mostly MSG? There are only different shapes and sizes of shards, no powders. I said MSG because thats the only substance i can think of that looks like keta shards. Ofcourse if its powder you can cut it with 1000 different things, but for "crystals" you are more limited. How do you spot it? My gut says the shards are 'too shiny', but i could be wrong. I will try and filter the large apart to see if the smaller ones are more potent.

If it isn't even K, what is it most likely then? I'm in northern EU. The effect was initially a bit like K, but then the effect is really vague, the blurry vision is there and some level of dissociation, but its not euphoric as K, and not psychedelic.