In the past, when I normally prospected platinum ore, I usually got about one rare gem per prospect of 5 ore. That still appears to work normally. However, mass prospecting gives quite different results.
A day or two ago I mass prospected 40 platinum ore and I got 1 rare gem (and 20 uncommon), which is way worse than what I’m used to with normal prospecting. Then I normally prospected another 40 platinum ore and I got 8 rare gems (and 13 uncommon), which is close to expected. Depending on how mass prospecting is supposed to work, this may or may not be a statistically significant difference; if I were doing normal prospecting on two different kinds of ore, it would be statistically significant. I wasn’t willing to test on substantially larger amounts of ore because I can’t afford to lose that much ore if mass prospecting continues to be that inferior.
This occurred on this character.
Steps to reproduce:
On a character with Kul Tiran jewelcrafting, obtain about 400 platinum ore.
Mass prospect 200 platinum ore, keeping track of the number of rare and uncommon gems obtained.
Normally prospect 200 platinum ore, keeping track of the number of rare and uncommon gems obtained.
If the difference in the number of gems obtained is more than 12, the difference is statistically significant, indicating a bug.
One possibility is that the total number of gems generated by mass prospecting is correct, but the number of rare gems is not adjusted for the larger number of ore prospected, making the number of rare gems 4x too low.
If a bug is found regarding rare gems, you should also check for a similar bug regarding epic gems. Testing for this would require prospecting a much larger amount of ore, though, on the order of 4000 ore.