A mineral is a naturally occurring chemical compound, usually of crystalline form and abiogenic in origin. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids. The study of minerals is called mineralogy.

There are over 5,300 known mineral species; as of March 2017, over 5,230 of these have been approved by the International Mineralogical Association (IMA). The silicate minerals compose over 90% of the Earth's crust. The diversity and abundance of mineral species is controlled by the Earth's chemistry. Silicon and oxygen constitute approximately 75% of the Earth's crust, which translates directly into the predominance of silicate minerals.

Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species, which were determined by the mineral's geological environment when formed. Changes in the temperature, pressure, or bulk composition of a rock mass cause changes in its minerals.

Minerals can be described by their various physical properties, which are related to their chemical structure and composition. Common distinguishing characteristics include crystal structure and habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, and specific gravity. More specific tests for describing minerals include magnetism, taste or smell, radioactivity and reaction to acid.

Minerals are classified by key chemical constituents; the two dominant systems are the Dana classification and the Strunz classification. The silicate class of minerals is subdivided into six subclasses by the degree of polymerization in the chemical structure. All silicate minerals have a base unit of a [SiO₄]⁴⁻ silica tetrahedron—that is, a silicon cation coordinated by four oxygen anions, which gives the shape of a tetrahedron. These tetrahedra can be polymerized to give the subclasses: orthosilicates (no polymerization, thus single tetrahedra), disilicates (two tetrahedra bonded together), cyclosilicates (rings of tetrahedra), inosilicates (chains of tetrahedra), phyllosilicates (sheets of tetrahedra), and tectosilicates (three-dimensional network of tetrahedra). Other important mineral groups include the native elements, sulfides, oxides, halides, carbonates, sulfates, and phosphates.

• Question: What is the cost of applying through ACASC?

Answer: ACASC charges a service fee of 50$ for using its online application portal. Applying through ACASC into Chinese universities attracts a service fee of $50.

• Question: Can I apply to the university directly?

Answer: Yes. ACASC gives the applicants, the chance to directly apply to their desired universities through our online application portal. We have synchronized our system to create a simple platform that connects universities and colleges in China to international students all around the world.

• Question: How can I track my application status?

Answer: To track the application status, please log in your ACASC personal account. Whenever there’s an update, you will be informed on your application status through ACASC system within a day as soon as we receive university’s notification. You will simultaneously receive ACASC auto-email about the application status. To directly inquire about your application status, feel free to send us an email toadmission@acasc.cn and our team will keep you updated.

• Question: How to deal with a pending application?

Answer: When an application is pending a decision it means that your school has received it and no admissions decision has been made yet. The admissions office may have reviewed your application package or may not have.

The main cause of a pending application is usually incomplete application documents. As a result you will be requested by the school’s admission office to re-check and modify all submitted application documents or perhaps even add extra documents and then re-submit them.

To avoid further delays, carefully read the university’s comments, modify your application form on ACASC, and re-upload the required application documents. You can contact ACASC on admission@acasc.cnfor any help with regards to your pending application

• How long does it take to process my application?

Answer: Processing time varies for different applications. For example to process a degree program application requires more time than a Chinese language application. Confirmation for Chinese language application by the admission office usually takes 2 to 4 weeks. However, time for degree programs application differs. For example fall semester application processing is after March, and it takes a period of 1 to 2 months. This also depends on your qualification and the number of applic