Convert from clove to arroba [Portugal]

Unit Definition (clove)
The clove is an old English unit of weight. A clove is usually considered equal to 1/2 stone or 1/16 hundredweight; that's 7 pounds (3.175 kilograms) by the modern definition of the stone, but in the past the clove varied from 6.25 to 8 pounds.

Unit Definition (arroba [Portugal])
The arroba [Portugal] is a traditional unit of weight in Spain and Portugal, equal to 1/4 quintal. However, the Spanish and Portuguese quintals are of different sizes. In Portugal and Brazil, the arroba traditionally equals 32.38 pounds (14.69 kilograms, but in recent years this has been "metrized" to be exactly 15 kilograms). The arroba has also been used as a metric unit equal to exactly 15 kilograms. The name of the unit comes from ar rub', Arabic for "the quarter."