To calculate the practical economic extractive tonnage from a stratiform deposit.
The extractive or forest industries of Brazil were among the first to engage the attention of Europeans, and have always been considered a principal source of colonial and national wealth.
When boiled in water the root affords a dark extractive matter, the quantity of extract yielded by the root being used as a criterion of its quality.
Oil obtained from heated meal is usually more highly coloured and harsher to the taste than cold drawn oil, more of the extractive substances being dissolved and intermixed with the oil.
Real larch turpentine is a thick tenacious fluid, of a deep yellow colour, and nearly transparent; it does not harden by time; it contains 15% of the essential oil of turpentine, also resin, succinic, pinic and sylvic acids, and a bitter extractive matter.