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GOST 8267-93 Crushed stone and gravel from dense rocks for construction works. Technical specifications (Changes No. 1-4)

GOST 8267-93 Crushed stone and gravel from dense rocks for construction works. Technical specifications (Changes No. 1-4).

 

 

GOST 8267-93

Group Ж17

 

 

INTERSTATE STANDARD

RUBBLE AND GRAVEL FROM DENSE ROCKS FOR CONSTRUCTION WORKS

Specifications

Crushed stone and gravel of solid rocks for construction works. Specifications

 

ISS 91.100.15

AXTU 5711

Date of introduction 1995-01-01

 


Preface

1 DEVELOPED by the Institute Vnipiistromsyre involving Vniigenetika, Nigba, Soyuzdornii Russian Federation

2 MADE by the Gosstroy of Russia

3 ACCEPTED by the Interstate scientific and technical Commission for standardization and technical regulation in construction (MNTKS) 10 November 1993

The adoption voted:

The name of the state The name of the government body construction
The Republic Of Azerbaijan Gosstroy Of The Republic Of Azerbaijan
The Republic Of Armenia Suprarenalectomy Of The Republic Of Armenia
The Republic Of Belarus Gosstroy Of The Republic Of Belarus
The Republic Of Kazakhstan The Ministry Of Construction Of The Republic Of Kazakhstan
The Kyrgyz Republic Gosstroy Of The Kyrgyz Republic
The Republic Of Moldova Minestry Of The Republic Of Moldova
Russian Federation The Gosstroy Of Russia
The Republic Of Tajikistan Gosstroy Of The Republic Of Tajikistan
The Republic Of Uzbekistan Moskomarhitektury Of The Republic Of Uzbekistan

4 ENTERED INTO force on 1 January 1995 as the state standard of the Russian Federation by the Resolution of Gosstroy of Russia from June, 17th, 1994 N 18-43

5 REPLACE GOST 8267-82, GOST 8268-82, 10260-82 GOST, GOST 23254-78, GOST 26873-86

6 EDITION (July 2018) with Changes No. 1, 2, 3, 4, adopted in February 1998, January 2000, June 2002, December 2008 (ICS 5-98, 5-2001, 10-2002, 6-2009)

 

Information about the changes to this standard is published in the annual reference index “National standards”, and the text changes and amendments – in monthly information index “National standards”. In case of revision (replacement) or cancellation of this standard a notification will be published in the monthly information index “National standards”. Relevant information, notification and lyrics are also posted in the information system of General use – on the official website of the Federal Agency for technical regulation and Metrology on the Internet (www.gost.ru)

 

1 Scope

This standard applies to crushed stone and gravel from rocks with an average density of grains 2.0 to 3.0 g/cm3, used as placeholders for heavy concrete, and for road and other construction works.

The standard does not apply to crushed stone and gravel for ballast layer of rail ways and decorative chippings.

The requirements set out in paragraphs 4.2 to 4.9, sections 5 and 6 are mandatory.

 

2 Normative references

The present standard features references to the following standards:

GOST 8269.0-97 Crushed stone and gravel from dense rocks and industrial waste products for construction works. Methods of physical and mechanical tests

GOST 8269.1-97 Crushed stone and gravel from dense rocks and industrial waste products for construction works. Methods of chemical analysis

GOST 30108-2016 Materials and products construction. Determination of specific effective activity of natural radionuclides.

(Changed edition, Rev. N 2).

 

3 Definitions

This standard applies the following terms.

3.1 crushed stone from rocks: Inorganic granular bulk material with grains of size St. 5 mm, received by crushing mountain rocks, gravel and boulders, incidentally produced Stripping and enclosing rocks or substandard waste mining enterprises for processing ores (ferrous, non-ferrous and rare metals metallurgy industry) and non-metallic minerals other industries, and subsequent sizing of crushing products.

3.2 gravel from rocks: Inorganic granular bulk material with grains of size St. 5 mm, obtained by screening natural gravel-sand mixtures.

 

4 Technical requirements

4.1 Crushed stone and gravel shall be manufactured in accordance with the requirements of this standard technological documentation approved by the manufacturer.

4.2. Basic parameters and dimensions

4.2.1 Crushed stone and gravel produced in the following main fractions: 5(3) 10 mm; St 10 to 15 mm; SV 10 to 20 mm; over 15 to 20 mm; over 20 to 40 mm; SV 40 to 80(70) mm and the mixture of fractions 5(3) up to 20 mm.

In coordination with the consumer release of crushed stone and gravel in the form of other mixtures made up of individual fractions and the fractions from 80(70) to 120 mm, over 120 to 150 mm.

4.2.2 Full remains on the test sieve after the sieving of crushed stone and gravel fractions 5(3) up to 10 mm over 10 to 15 mm, over 10 mm to 20 mm, over 15 to 20 mm over 20 to 40 mm over 40 to 80(70) mm and the mixture of fractions 5(3) up to 20 mm shall be as specified in table 1, where d and D are the smallest and largest nominal size of the grains.

Table 1

Diameter of apertures of test sieves, mm d 0,5(d + D) D 1,25 D
Full the remains on the sieve, % by mass From 90 to 100 From 30 to 60 To 10 To 0.5
Notes

1 For crushed stone and gravel fractions 5(3) to 10 mm and the mixture of fractions 5(3) up to 20 mm are used in addition: the lower sieve 2.5 mm (1.25 mm), total balance of which should be from 95% to 100%.

2 By agreement with the consumer allowed to produce crushed stone and gravel with full residue on sieve 0,5(d + D) from 30% to 80% by weight.

4.2.3 For crushed stone and gravel fractions of over 80(70) to 120 mm and over 120 to 150 mm, and the mixture fractions produced by agreement between manufacturer and consumer, the complete balances on control sieves of diameter d, D, of 1.15 D must satisfy given in table 1, and the ratio of fractions in the mixtures is determined by agreement between manufacturer and consumer in accordance with the regulations on the use of these mixtures for construction work.

4.2.1-4.2.3 (Revised edition, Edit. N 3).

4.2.4 (Deleted, Rev. N 3).

4.3 the Content of crushed grains in gravel gravel and boulders and form beans

4.3.1 Crushed gravel and boulders should contain crushed grain in an amount of not less than 80% by weight. Permitted by agreement with the consumer release of crushed gravel with the content of crushed grains is not less than 60%.

(Changed edition, Rev. N 4).

4.3.2 the Form of grains of crushed stone and gravel characterize the content of grains of lamellar (flake) and hlavaty form.

Crushed stone depending on the content of grains of lamellar and hlavaty forms are divided into five groups, which should correspond to those in table 2.

Table 2

Group of rubble The content of grains of lamellar (flake) and hlavaty forms, % by mass Group of rubble The content of grains of lamellar (flake) and hlavaty forms, % by mass
1 To 10 incl. 4 SV. 25 to 35 incl.
2 SV. 10 to 15 incl. 5 ” 35 ” 50 “
3 ” 15 ” 25 “
Note – By agreement with the consumer allowed the production of crushed stone from igneous rocks containing over 50 % but not more than 65% of grains of lamellar (flake) and hlavaty form.

(Changed edition, Rev. N 3).

4.3.3 the Gravel should not contain grains of lamellar and hlavaty forms more than 35% by weight.

4.4 Strength

4.4.1 the Strength of crushed stone and gravel characterize the brand name for divisibility by compression (crushing) in a cylinder.

(Changed edition, Rev. N 4).

Crushed stone and gravel, intended for construction of automobile roads, characterize the brand name for divisibility by compression (crushing) in a cylinder and a mark of abrasion, determined by the test in the drum shelf.

4.4.2 grade shatter rubble from sedimentary and metamorphic rocks shall conform to the requirements specified in table 3, and grade shatter rubble from igneous rocks in table 4.

Table 3

Mark on the divisibility of gravel from sedimentary and metamorphic rocks Mass loss during the test gravel %
in the dry state in water saturated state
1200 To 11 incl. To 11 incl.
1000 SV. 11 to 13 SV. 11 to 13
800 ” 13 ” 15 ” 13 ” 15
600 ” 15 ” 19 ” 15 ” 20
400 ” 19 ” 24 ” 20 ” 28
300 ” 24 ” 28 ” 28 ” 38
200 ” 28 ” 35 ” 38 ” 54

Table 4

Mark on the divisibility of rubble from igneous rocks Mass loss during the test gravel %
of Intrusive rocks of effusive rocks
1400 Up to 12 cyl. To 9 incl.
1200 SV. 12 to 16 SV. 9 to 11
1000 ” 16 ” 20 ” 11 ” 13
800 ” 20 ” 25 ” 13 ” 15
600 ” 25 ” 34 ” 15 ” 20

Allowed to determine the grade of gravel from sedimentary and metamorphic rocks in dry and water saturated state.

When you mismatch brands for divisibility durability evaluate the results of tests in water saturated state.

Brand for divisibility of crushed gravel and gravel shall conform to the requirements specified in table 5.

Table 5

Mark on the divisibility of crushed gravel and gravel Mass loss during the test, %
crushed stone gravel gravel
1000 To 10 incl. To 8 incl.
800 SV. 10 to 14 SV. 8 to 12
600 ” 14 ” 18 ” 12 ” 16
400 ” 18 ” 26 ” 16 ” 24

To establish the brand in the shatter rubble of boulders, consisting of rocks of various genetic types, determined according to GOST 8269.0 intermediate brand for divisibility as a weighted average of the marks obtained, separately for gravel these rocks based on their content in the rubble of boulders. Weighted average Marche establish a brand of shatter rubble of boulders in table 5A.

Table 5A

Intermediate weighted average mark for divisibility of gravel from the boulders Mark shatter rubble of boulders
1200 and above 1200
SV. 1000 to 1200 1000
SV. 800 to 1000 800
SV. 600 to 800 600
SV. 400 to 600 400
SV. 300 to 400 300

(Changed edition, Rev. N 4).

4.4.3 Brand of abrasion of crushed stone and gravel shall conform to the requirements specified in table 6.

Table 6

Mark of abrasion of crushed stone and gravel Mass loss during the test, %
crushed stone gravel
I1 Up to 25 incl. Up to 20 incl.
I2 SV. 25 to 35 SV. 20 to 30
U3 ” 35 ” 45 ” 30 ” 40
I4 ” 45 ” 60 ” 40 ” 40

4.5 the Content of grains of weak rocks

The content of weak rock grains in crushed stone and gravel, depending on the kind of rock and stamps for divisibility should not be more than specified in table 7.

Table 7

Of a breed and mark for divisibility of crushed stone and gravel The content of weak rock grains, % by mass
The crushed stone from igneous, metamorphic and sedimentary rocks brands:
1400; 1200; 1000 5
800; 600; 400 10
300 15
Crushed gravel and boulders and gravel grades:
1000; 800; 600 10
400 15

4.6 Frost

4.6.1 Frost resistance of crushed stone and gravel characterize the number of cycles of freezing and thawing, where the loss in mass percent of crushed stone and gravel do not exceed the set values.

Allowed to assess the frost resistance of crushed stone and gravel by the number of cycles of saturation in sodium sulfate solution and drying. When you mismatch brands of frost resistance is evaluated by the test results of freezing and thawing.

4.6.2 Crushed stone and gravel on frost resistance are divided into the following grades: F15, F25, F50, F100, F150, F200, F300, F400.

Indicators of frost resistance of crushed stone and gravel, when tested, freezing and thawing or saturation in sodium sulfate solution and drying shall be as specified in table 8.

Table 8

Type of test Mark on frost resistance of crushed stone and gravel
F15 F25 F50 F100 F150 F200 F300 F400
The freezing-thawing:
– the number of cycles 15 25 50 100 150 200 300 400
– mass loss after test, %, not more 10 10 5 5 5 5 5 5
The saturation in solution of sodium sulfate is dried:
– the number of cycles 3 5 10 10 15 15 15 15
– mass loss after test, %, not more 10 10 10 5 5 3 2 1

4.7 the Content of dust and clay particles

4.7.1 Content of dust and clay particles (smaller than 0.05 mm) in gravel or gravel depending on the kind of rock and stamps for divisibility shall be those specified in table 9.

Table 9

Of a breed and mark for divisibility of crushed stone and gravel The content of dust and clay particles,%, by mass, not more
The crushed stone from igneous and metamorphic rocks of the stamps:
St. 800 1
St. 600 to 800 incl. 1
Pebbles of sedimentary rocks brands:
from 600 to 1200 incl. 2
200, 400 3
Crushed gravel and gravel grades:
1000 1
800 1
600 2
400 3
Rubble of boulders marks:
1200 1
1000 1
800 1
600 2
400 3

(Changed edition, Rev. N 4).

4.7.2 the Content of clay in lumps should not be more than specified in table 10.

Table 10

Mark on the divisibility of crushed stone and gravel The content of clay lumps, % by mass, not more
The crushed stone from igneous, sedimentary and metamorphic rocks grades:
400 and above 0,25
300, 200 0,5
Crushed gravel and gravel grades:
1000, 800, 600, 400 0,25
Rubble of boulders marks:
1200, 1000, 800, 600 0,25

(Changed edition, Rev. N 4).

4.8 the Presence of harmful components and impurities

4.8.1 Gravel produced overburden and host rocks and substandard waste mining enterprises for processing ores (ferrous, non-ferrous and rare metals metallurgy industry) and non-metallic minerals other industries should be resistant against all types of decay.

Structure stability of rubble against all types of decay must comply with the requirements specified in table 11.

Table 11

Mark shatter rubble Mass loss in the decay, %, not more
1000 and above 3
800, 600 5
400 and below 7

4.8.2 Crushed stone and gravel needs to be resistant to the environment. Crushed stone and gravel intended for use as aggregates for concrete, shall be resistant to chemical attack of alkalis of cement.

Durability of crushed stone and gravel is determined by the mineralogical-petrographic composition of the source rocks and the content of hazardous components and impurities that reduce the durability of concrete and cause corrosion of rebar reinforced concrete products and structures.

The list of harmful components and their allowable content is given in Appendix A.

4.9 in the production of crushed stone and gravel must be radiation-hygienic assessment, the results of which set the scope. Crushed stone and gravel, depending on the values of the total specific effective activity of natural radionuclides Aeff is used:

– in Aeff to 370 Bq/kg in newly-built residential and public buildings;

– if Aeff St 370 to 740 Bq/kg for road construction in the territory of settlements and areas of promising development, and also in the construction of industrial buildings and constructions;

if Aeff St. 740 to 1500 Bq/kg in road construction outside the settlements.

If necessary, the national rules in force in the territory of the state, the value of specific effective activity of natural radionuclides can be changed within the limits specified above.

(Changed edition, Rev. N 1, 2).

4.10 Crushed stone and gravel shall not contain extraneous contaminating impurities.

4.11 Security set standard values of quality crushed stone and gravel on the grain composition (content of granules smaller than the smallest nominal size d or more the largest nominal size D) and the content of dust and clay particles should be not less than 95%.

 

5 acceptance Rules

5.1 Crushed stone and gravel should be taken by the technical control of the manufacturer.

5.2 the Acceptance and delivery of crushed stone and gravel produced by the parties. Party consider the amount of crushed stone (gravel) one fraction (the mixture fractions) specified in the contract for the supply and at the same time shipped to a single consumer in a single train or single vessel. When shipping by road transport by party count the number of crushed stone (gravel) one fraction (the mixture fractions) which are supplied to one consumer in one day.

5.3 To check the quality of crushed stone (gravel) the requirements of this standard, conduct acceptance testing and periodic testing.

Acceptance inspection at the factory is carried out daily by testing the combined sample of crushed stone (gravel) selected on each processing line. During acceptance inspection will determine:

– grain structure;

– the content of dust and clay particles;

– the content of clay in lumps;

– the content of grains of weak rocks.

5.4 periodic testing determine:

– once in 10 days – the content of grains of lamellar and hlavaty form and content of crushed grains in gravel gravel and boulders and the concentration of free asbestos fibers in the crushed asbestos-containing rocks;

– once a quarter – strength and bulk density, structure stability against decays;

– once a year – and frost resistance class of crushed stone (gravel) on the value of specific effective activity of natural radionuclides, as well as on-demand consumers, the content of hazardous components and impurities.

The value of the specific effective activity of natural radionuclides is determined, and the grade of crushed stone and gravel are installed in specialized laboratories for the certified gamma-spectrometric installations or radiation-metric laboratories of supervisors.

In the absence of data exploration in radiation-hygienic evaluation of the Deposit and the conclusion of the grade of crushed stone and gravel, the manufacturer conducts a preliminary evaluation of the developed parcel of rocks directly at the quarry or gravel (gravel) in stock of finished products in accordance with GOST 30108.

Strength, frost resistance of crushed stone and gravel, as well as the structure stability of rubble against all types of decay is determined in each case modify the properties of raw materials (rocks, produced rocks and industrial wastes).

In the absence of data of the geological exploration of the content of hazardous components and impurities of the enterprise is conducted in specialized or accredited laboratories and test centers, by definition in the production of reactive rocks, the content of weak grains and impurities of metal in the rubble from slags black and nonferrous metallurgy, slag activity and dielectric properties of crushed stone for ballast layer of railway track.

(Changed edition, Rev. N 2, 4).

5.5 the Selection and preparation of samples of crushed stone (gravel) for quality control at the factory is carried out in accordance with the requirements of GOST 8269.0, GOST 8269.1.

The control point for a preliminary assessment of the rocks and the grade of crushed stone and gravel choose according to GOST 30108.

5.4, 5.5 (Revised edition, Edit. N 2).

5.6 the user with control and verification of compliance of crushed stone (gravel) the requirements of this standard shall apply is given in 5.7-5.10, the order of sampling.

5.7 the Number of point samples taken by the consumer to control the quality of crushed stone (gravel) in each lot depending on the lot size shall be not less than:

up to 350 m3 10
over 350 up to 700 m3 15
” 700 m3 20

From point samples to form a combined sample, characterizing the controlled batch. Averaging, reduction and preparation of samples for testing carried out in accordance with GOST 8269.0, GOST 8269.1.

(Changed edition, Rev. N 2).

5.8 For quality control of crushed stone and gravel, shipped by rail, spot samples are taken during unloading of cars from a flow of crushed stone (gravel) on the tape containers used for transporting it to the warehouse of the consumer. When unloading each oprobyvat of the car taken after equal time intervals of five spot samples. The number of cars is determined based on the desired number of point samples 5.8. Cars choose at the direction of the consumer. In case consignment consists of one car, while unloading select five spot samples from which the combined sample.

If the conveyor transport when unloading of cars is not used, then point samples are taken directly from the cars. For this purpose a surface of crushed stone (gravel) in the car level and the sampling point off the wells with a depth of 0.2-0.4 m sampling Points should be located in the center and four corners of the car, the distance from the sides of the car to the sampling points should be at least 0.5 m From the wells, samples of gravel taken away the shovel, moving it upward along the wall of the hole.

5.9 To control the quality of crushed stone (gravel), water supply transport, spot samples are taken during unloading of ships.

In the case of the unloading belt conveyors spot samples are taken after equal time intervals from a stream of crushed stone (gravel) on the conveyor. When the ships were unloaded by grab cranes, spot, scoop samples are taken at regular intervals of time as unloading directly from the newly formed surface of crushed stone (gravel) in the ship, not the hole.

5.10 To control the quality of crushed stone (gravel) shipped by road, spot samples are taken during unloading of the cars.

In the case of the unloading of crushed stone (gravel) belt conveyors spot samples are taken from stream gravel on the conveyor. During the unloading of each car take a single point sample. The number of cars will be based on achieving the required number of point samples 5.7. Cars choose at the direction of the consumer.

If the party comprises less than 10 cars, then crushed stone samples taken from each car.

If the conveyor transport when unloading of cars is not used, spot samples are taken directly from vehicles. For this purpose a surface of crushed stone (gravel) in the car even in the center of the body off the hole to a depth of 0.2-0.4 m From the hole a sample of crushed stone (gravel) take a shovel, moving it upward along the hole.

5.11 the Number of delivered crushed stone (gravel) is determined by the volume or mass. Measurement of crushed stone (gravel) is carried out in wagons and cars.

Crushed stone (gravel) shipped in cars or vehicles are weighed on rail or truck scales. Weight of crushed stone (gravel) shipped in the courts, determine the vessel’s draught. The amount of crushed stone (gravel) from mass units to volume units counted on the value of the bulk density of crushed stone (gravel), determined by its humidity during the shipment.

The volume of the crushed stone (gravel) that is included in the car or vehicle is determined by measurement, the obtained volume is multiplied by a compaction factor of crushed stone (gravel) when transporting, which depends on the loading method, the distance of transportation of grain structure. The maximum permissible moisture value and the compression ratio that should not exceed of 1.10, set in the purchase contract.

5.12 the results of the acceptance inspection and the periodic testing lead to a quality document in which you specify:

– the name of the manufacturer and his address;

– number and date of issuance of the document;

– the name and address of the consumer;

– the batch number and the quantity of crushed stone (gravel);

– the number of the wagon or number of the vessel and numbers of invoices;

– grain composition of the crushed rock (gravel);

– the content of grains of lamellar (flake) and hlavaty form;

– the content of crushed grains in crushed gravel;

– the content of clay in lumps;

– Marc gravel (gravel) strength (shatter);

– the content of dust and clay particles;

– the content of grains of weak rocks;

– frost resistance of crushed stone (gravel);

– bulk density of crushed stone (gravel);

specific effective activity of natural radionuclides of crushed stone (gravel);

– structure stability of rubble against decay;

– the content of hazardous components and impurities;

– the designation of this standard.

In addition, at the request of the consumer in the document indicate mineralogical and petrographic characteristics of the gravel and rocks, which produce crushed stone, as well as true density, porosity, voidage and water absorption.

(Changed edition, Rev. N 4).

 

6 Methods to control

6.1 Testing of crushed stone and gravel is carried out according to GOST 8269.0, GOST 8269.1.

When determining the grain composition of the crushed stone and gravel is allowed to use a sieve with apertures of 70 mm to equipping enterprises with sieves with openings of 80 mm.

6.2 structure Stability of rubble against all types of decay determined according to GOST 8269.0.

6.1, 6.2 (Revised edition, Edit. N 2).

6.3 Specific efficient activity of natural radionuclides in rubble and gravels is determined by gamma-spectrometry GOST 30108.

6.4 Security set standard values of the content in the crushed stone and gravel of grain size less than the smallest nominal size d or more the largest nominal size D and the content of dust and clay particles characterized by the ratio of the number of replacement samples, the quality indicators that exceed regulatory values, to the total number of replacement samples taken and tested within the same block.

 

7 Transportation and storage

7.1 Crushed stone and gravel is transported in bulk in vehicles of any kind according to the rules of carriage of goods and technical regulations of loading and fastening of cargoes, approved by the Ministry of Railways, rules of carriage of goods by road and water transport.

During the transportation of crushed stone and gravel rail cars to load with the full use of their capacity.

7.2 Crushed stone and gravel are stored separately on shares and mixtures of fractions in terms of preventing them from clogging and contamination.

 

Annex a (mandatory) the Content of hazardous components and impurities

APPENDIX A
(required)

 

1 To major components, reducing the strength and durability of concreteinclude the inclusion of:

– clay minerals (montmorillonite, kaolinite, etc.);

– micas and hydromicas and other layered silicates;

asbestos;

– organic substances (coal, lignite, oil shale, humic acids, etc.);

– minerals resistant to weathering processes (chlorite, zeolite, Apatite, nepheline, phosphorite).

2 the main components that causes deterioration of the surface and internal corrosion of the concrete, include the inclusion of:

– rocks and minerals, containing amorphous varieties of silica (chalcedony, opal, etc.);

– sulfur-containing rocks and minerals (pyrite, marcasite, pyrrhotite and other sulphides, as well as gypsum, anhydrite and other sulfates);

– rocks and minerals containing oxides and hydroxides of iron (magnetite, goethite etc.);

– micas, hydromicas and other layered silicates.

3 the main components that cause corrosion of reinforcement in concreteinclude the inclusion of halogenated minerals (pyrite, marcasite, pyrrhotite and other sulphides, gypsum, anhydrite and other sulphates).

4 Crushed stone and gravel used in concrete without limitations if the content of rocks and minerals, attributable to the harmful components is not more than:

50 mmol/l of amorphous varieties of silica, soluble in alkalis;

A 1.5% by weight of sulphates (gypsum, anhydrite) and sulfides besides pyrite (marcasite, pyrrhotite, gypsum, anhydrite, etc.) in SO3;

4% by mass of pyrite;

15% by volume of the layered silicates, if mica, hydrology, chlorite, and others are rock-forming minerals;

Of 0.1% by weight of the halides (halite, sylvite, etc., including water-soluble chlorides) in terms of chlorine ion;

0,25% by weight of free fibres of asbestos;

1.0 percent by weight of coal and wood residues;

10% by volume of each of these rock-forming minerals (magnetite, goethite, hematite, etc., Apatite, nepheline, phosphorite), or their sum in the amount of not more than 15%.

 

APPENDIX B (Excluded Mod. N 2).

 

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