Vaisesika Sūtra 2.2.01

पुष्पवस्त्रयोः सति सन्निकर्षे गुणान्तराप्रादुर्भावो वसत्र गन्धाभावलिङ्गम् ॥१॥

When the flower and garment that are together are brought to proximity, the disappearance of fragrance from the garment is the distinguishing mark.

Nature of distinguishing mark is being explained.