Anbs'h bin Khalid bin Yazid عنبسة بن خالد بن يزيد · Commercial Transactions (Kitab Al-Buyu)

The Prophet (ﷺ) forbade the sale of grapes till they became black and the sale of grain till it had become hard.

"Wearing the samma' means that a man puts his garment over his left shoulder and keeps his right side uncovered. Munabadhah means that a man says (to another): If I throw this garment to you, the sale will be certain. Mulamasah means that a man touches it (another's garment) with his hand and neither he unfolds it nor turns it over. When he touched it, the sale becomes binding.