磁石

English text reference: Chinese Pharmacopoeia (2020 Edition)

Overview

Magnetite is the oxide mineral of the spinel group, mainly composed of ferrous ferric oxide (Fe3O4). After mining, it is purified by removing impurities.

Description

Magnetite is a block-like aggregate, irregularly shaped or slightly square, often with edges and corners. It is gray-black or brownish-black, with a black streak and metallic luster. It is heavy, hard, and has an uneven fracture. It is magnetic and has an earthy odor and a mild taste.

Identification

Take about 0.1g of the powder, add 2ml of hydrochloric acid, shake and let it stand. The clear liquid shows the identification reaction of iron salt (General Rule 0301).

Content Determination

Take about 0.25g of the fine powder, accurately weigh it, place it in a conical flask, add 15ml of hydrochloric acid and 3ml of 25% potassium fluoride solution, cover with a surface dish, heat to a slight boil, add 6% stannous chloride solution dropwise, shake continuously, wait for complete decomposition, leaving only white residue at the bottom of the bottle, remove it, rinse the surface dish and the inner wall of the bottle with a small amount of water, and while it is still hot, add 6% stannous chloride solution dropwise until it appears light yellow (if stannous chloride is excessive, dropwise add potassium permanganate solution until it appears light yellow), add 100ml of water and 15 drops of 25% sodium tungstate solution, and dropwise add 1% titanium trichloride solution until it appears blue, then carefully add potassium dichromate titration solution (0.01667mol/L) until the blue color just fades away, immediately add 10ml of sulfuric acid-phosphoric acid-water (2:3:5) and 5 drops of sodium diphenylamine sulfonate indicator solution, and titrate with potassium dichromate titration solution (0.01667mol/L) until the solution appears stable blue-purple. Each 1ml of potassium dichromate titration solution (0.01667mol/L) is equivalent to 5.585mg of iron (Fe).

The iron (Fe) content in magnetite should not be less than 50.0%.

Prepared Slices

Magnetite

Processing

Remove impurities and crush.

Description

Magnetite prepared slices are irregular fragments. They are gray-black or brownish-black, with a black streak and metallic luster. They are hard in texture, magnetic, and have an earthy odor and a mild taste.

Identification

Same as the crude drug.

Content Determination

Same as the crude drug.

Calcined Magnetite

Processing

Take clean magnetite blocks, calcine them according to the calcination and quenching method (General Rule 0213) until they are red and translucent, quench with vinegar, and grind into coarse powder.

Vinegar 30 kg per 100 kg magnet.

Description

Calcined magnetite is irregular fragments or particles. The surface is black. It is hard and brittle in texture. It is non-magnetic. It has a vinegar aroma.

Content Determination

Same as the crude drug. The iron (Fe) content should not be less than 45.0%.

Identification

Same as the crude drug.

Property

cold.

Flavor

salty.

Meridian tropism

It enters the Liver, Heart, and Kidney meridians.

Actions

It calms the mind, soothes the Liver and suppresses Yang, sharpens the hearing and improves vision, and regulates Qi and relieves asthma.

Indications

It is used for palpitations and insomnia, dizziness and vertigo, blurred vision, tinnitus and deafness, and deficiency of the Kidney with Qi wheezing.

Dosage

9-30g.

Administration

decoct first.

Storage

Store in a dry place.

磁石

Text reference: Chinese Pharmacopoeia (2015 Edition)

Overview

Magnetite is a mineral of oxides of spinel group, containing mainly ferroferric oxide(FeO).The drug is collected, removed from foreign matter.

Description

Aggregates of masses, in irregular masses, or slightly subsquare, frequently with angularities.Greyish-black or brown; streak black, with lustre of metal.Texture hard and heavy, fracture uneven.Magnetic.Odour, earthy; tasteless.

Identification

To 0.1 g of the powder add 2 ml of hydrochloric acid, shake, allow to stand.The supernatant yields the reactions characteristic of ferric and ferrous salts〈0301〉.

Assay

本品含铁（Fe）不得少于50.0%。

Prepared slices

Magnetite

Processing

Magnetitum Eliminate foreign matter, pound to pieces.

In irregular masses, greyish-black or brown, streak black, with luster of metal. Texture hard and heavy. Magnetic. Odour, earthy; tasteless.

Identification

【Assay】As required for the crude drug.

Magnetitum (calcined)

Calcine the clean Magnetitum as described under the method for calcining and quenching 〈0213〉 to red thoroughly, quench with vinegar and grind to coarse powder, using 30 kg of vinegar per 100 kg of Magnetitum.

In irregular masses or granules, externally black. Texture hard and crisp, non-magnetic. Odour, vinger aromatic.

Identification

【Assay】As required for the crude drug. It contains not less the than 45.0 per cent of Iron (Fe), following the method for the crude drug.

Property and Flavor

Cold; salty. Liver, heart and kidney meridians.

Actions and Indications

To settle fright, tranquilize the mind, pacify the liver, subdue yang, improve audition and vision, absorb qi, and relieve wheezing. Fright palpitations, insomnia, diziness, vertigo, blurry vision, tinnitus, deafness, wheezing caused by kidney deficiency.

Administration and dosage

9-30 g.It should be decocted first.

Storage

Preserve in a dry place.