The quality of the triad you are describing is a major triad.
In a major triad:
- The interval from the root to the third is a major third (M3).
- The interval from the third to the fifth is a minor third (m3).
However, in your question, you mentioned the interval between the root and third is a minor third (m3), which is not correct. Thus, it should be clarified.
If you truly have a minor third (m3) from the root to the third and a major third (M3) from the third to the fifth, then the triad would be a minor triad.
To sum up:
- If the interval from root to third is a minor third (m3) and from third to fifth is a major third (M3) → it is a minor triad.
- If the interval from root to third is a major third (M3) and from third to fifth is a minor third (m3) → it is a major triad.
Based on your original information, it seems you're describing a minor triad.