It‘s white in color, but kind of clear at the same time. It shimmers like CRAZY when it reflects light. Kind of looks like a chunk of ice.
By it looks like a chunk of ice i'll assume you mean it has cleavage. Though it doesn't reflect light like crazy but i believe that the rock your talking about is halite or calcite.
There's about a 95% chance it's either quartz or a carbonate mineral (usually calcite/dolomite). Drop hydrochloric acid on it. If it effervesces, it's calcite. If it fizzes a tiny bit, it's likely dolomite. If it doesn't do a thing, it's likely quartz. It's very unlikely to be any of the following minerals (listed by people above): Phenakite, aragonite, gypsum, quartzite,
My brain? just kidding, phenakite? calcite? quartz? number one choice aragonite! dolomite gypsum or maybe a combination of calcite and dolomite Why the curiosity? Precious gem! (congrats on the 2000 points)
