Is it Calcite or Aragonite?

Acicular Aragonite or is it Calcite? Otherwise known as "Root beer Aragonite" on the market, these specimens originate from the Hunan Province in China. When it comes to calcite or aragonite there is such a fine line between the two minerals. More specifically, calcium carbonate can take two forms: calcite in a stable form or aragonite which is metastable. Depending on heat or water, it can become either calcite or aragonite.
I was on team calcite on this one. And according to the test results you can view below, these specimens "show rhombohedral cleavage, thus, the specimen is dominantly calcite with a little aragonite present." So calcite is its dominant material with some aragonite present. Also, I had wondered why these were not fluorescent and now we know why, because of the high iron content.
So it is probably more accurate to call these calcite.

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