Pound-based Vs. Kilogram-based
The concept has resulted in two different series of masses: Those based on the local pound (which after metrication was considered equivalent to half a kilogram), and those uprated to being based on the kilogram.
In India and Albania (kuintal), the quintal as equivalent to 100 kilogram was imported via Arabic influence and is a standard measurement of mass for agricultural products.
In France it used to be defined as 100 livres (pounds), about 48.95 kg, and has been redefined as 100 kg (mesures usuelles), thus called metric quintal with symbol qq.
In Spain, the centena is still defined as 100 libras, or about 46 kg, but the metric quintal is also defined as 100 kg;
In Portugal a quintal is 128 libras or about 58.75 kg.
The German Zentner is pound-based, and thus since metrication is defined as 50 kg, whereas the Austrian and Swiss Zentner since metrication has been re-defined as 100 kg.
Common agricultural units used in the Soviet Union were the 100-kilogram centner (центнер) and the term "centner per hectare". These are still used by countries that were part of the Soviet Union.
Read more about this topic: Quintal