Quartz vein type gold ore beneficiation process

There are many types of gold deposits in nature. Different types of gold mines contain different elements. Naturally, the selected beneficiation process is also different. The common types of gold deposits are: broken zone altered rock type, quartz vein type and volcanic subvolcanic hydrothermal type, followed by veinlet disseminated type (granite type), structural altered rock type, iron cap type and so on.

The industrial types of gold deposits can be divided into three categories: rock (vein) gold deposits, placer gold deposits and associated gold deposits. Statistics show that the number and gold reserves of quartz vein gold deposits account for more than 50% of the total number of gold deposits and the total gold reserves in China.

Types of Quartz Vein Type Gold Deposits and Their Beneficiation Methods

Category 1: Quartz gold-bearing ore

Gold-bearing ore containing a small amount of sulfide, more than 90% of the ore is quartz, the metal mineral is natural gold, almost no other sulfide, and the gold grains are mostly coarse.

Beneficiation process: Coarse particles can be recovered by gravity separation; fine particles can be recovered by full-slime cyanidation.

Category 2: gold and sulfide paragenetic ore

Metal minerals are mainly pyrite. The sulfide content is 1 to 5%; the gangue is mainly quartz; more than 60% of natural gold is symbiotic with sulfide. Gold is mainly medium and fine grained.

Mineral processing technology: cyanidation method and flotation method are the main methods, and the cyanidation process of flotation fine sand is commonly used.

Category 3: gold and quartz symbiotic ore

There are few metal sulfides, and more than 70% of gold is symbiotic with gangue minerals such as quartz. Generally, the particle size is finer.

Mineral processing process: mainly cyanidation and flotation. Amalgamation and gravity separation assist recovery of coarse-grained gold.

Category 4: Pyrite gold-bearing quartz vein ore

The main mineral is pyrite, the main difference is that the sulfide content accounts for 5-15%; 75-99% of gold is symbiotic with pyrite.

Mineral processing technology: flotation, the recovery rate of gold is over 95%, but the grade of gold in the flotation concentrate is low.

Category 5: Quartz vein gold-bearing oxide ore

Quartz vein gold-bearing oxide ores are divided into partially oxidized ores and fully oxidized ores. The main metal mineral is limonite, followed by a small amount of pyrite. The gangue is quartz. Gold exists in mineral fractures. It is characterized by containing gold in iron hydroxide. Contains sulfides. Most of the gold occurs in gangue minerals and metal oxide residual particles after weathering, and the ore contains mud.

Mineral processing technology: Coarse gold is recovered by amalgamation and gravity separation. Slime is stirred for cyanidation, and ore sand is percolated for cyanidation.