The Conditions For Determining The Individual Types Of Crystal Glass

Original Language Title: podmínky pro určování jednotlivých druhů křišťálového skla

Read the untranslated law here:

Subscribe to a Global-Regulation Premium Membership Today!

Key Benefits:

Subscribe Now for only USD$20 per month, or Get a Day Pass for only USD$4.99.
379/2000 Sb.


The Ministry of industry and trade

of 10 June 1999. October 2000,

laying down the conditions for the determination of individual types of Crystal

glass, their properties and the methods of labelling of products from Crystal


The Ministry of industry and trade shall be determined according to section 28a (e). (f)) of law No.

634/1992 Coll. on consumer protection, as amended by Act No. 103/1995 Coll. and

Act No. 64/2000 Coll.:

§ 1

(1) the Decree lays down the conditions for the determination of each of the species

Crystal glass, including the names of the following species, properties that is

characterize, they added symbols and methods of measurement for the

chemical and physical properties, as well as the conditions for marking

Crystal glass products including the identification of products from Crystal

glass, which are subject to labelling.

(2) the labelling shall apply to the products of each type of Crystal

the glass included in the code number of the harmonised system customs 7013

nomenclature. ^ 1)

(3) the individual types of crystal glass are referred to by these names:

and) highly leaded Crystal 30% PbO,

b) leaded Crystal 24% PbO,

c) crystal glass krystalin, or

d) crystal glass.

(4) the conditions for determining the individual types of crystal glass and the way

marking are listed in annex 1.

(5) the methods for determining the chemical and physical properties of the individual

types of crystal glass are given in annex 2.

§ 2

The name of the type and symbol according to annex No 1 can only be used for individual

types of crystal glass, if they fulfil the conditions laid down in this

the annex.

§ 3

The names of the types of crystal glass and symbols referred to in annex 1,

be placed together on one label.

§ 4

Where commercial designation, name of the manufacturer, importer or seller

or any other mark or part thereof would be identical or

similar with the designation of the individual types of crystal glass under this

the Decree, or would have them give rise to any confusion, both in the

menu and in the commercial documentation, and in the advertising of such products,

marks before the placing on the market in such a way as to

and) for each type of crystal glass, it was possible to conclusively determine

whether they meet the requirements set out in section 2, and

(b)) products that do not meet the requirements referred to under (a)), have not been

bear the symbol and the name of the Crystal glass according to annex No 1;

such product shall be marked in accordance with its properties.

§ 5

The effectiveness of the

This Decree shall enter into force on 1 January 2000. January 1, 2001.


doc. Ing. Gregr, r.

Č. 1

The conditions for determining the individual types of crystal glass and the way

their labelling

Č. 2






Bao and PbO

1.1.1 establishment of the combination BaO + PbO

In a Platinum dish to the nearest 0.0001 g weigh approximately 0.5 g

gently rozetřeného the glass. After wetting with water, add 100 ml of a 15% solution

10 ml of sulphuric acid and hydrofluoric. Then heat up the sand

bath, to begin to develop white fumes. When cool, add 10 again

ml of hydrofluoric acid and heat until the development of the White

fumes. Allow to cool, the sides of the dish with water and heat,

to begin to develop white fumes. When cool, carefully add 10 ml and

the contents of the bowl into a beaker 400 ml. Rinse the dish several times

10% solution of sulphuric acid and dilute with the same solution to a volume of 100

ml. Solution precipitate boil 2 to 3 minutes. Then allow to stand

for at least 12 hours.

The precipitate is filtered filter crucible of porosity 4 wash

first 10% sulphuric acid solution, then two to three times

with ethyl alcohol. Crucible with precipitate is dried in an oven at 1 hour

150 degrees C weigh the BaSO4 + PbSO4.

1.1.2 establishment of BaO

In a Platinum dish to the nearest 0.0001 g weigh approximately 0.5 g

gently rozetřeného the glass. After wetting with water, add 10 ml of acid

5 ml of hydrofluoric and perchloric acid and heat on the sand bath,

to begin to develop white fumes.

After cooling, add a further 10 millilitres hydrofluoric acid and heat

the development does not occur again until white fumes. Allow to cool and

the walls of the bowl is rinsed with distilled water. Heat again and

evaporate almost to dryness. Dissolve in 50 ml of 10% solution

hydrochloric acid and heat gently to facilitate

dissolving. Transfer the solution into the beaker, 400 ml and dilute with water to

volume 200 ml. Heat until boiling and blows the hot stream of hydrogen sulphide.

The supply of hydrogen sulfide shall cease when the lead sulphide precipitate

falls to the bottom of the beaker. The precipitate is filtered through a fine filter

paper and wash with cold water saturated with hydrogen sulphide.

Bring to a boil the filtrate and then, if necessary, a reduction in volume

by evaporation to 300 ml. To boiling mixture, add 10 ml of 10% solution

sulphuric acid and remove from the heat source. After at least

čtyřhodinovém stall, the precipitate is filtered through a fine filter paper and

wash with cold water. Calcine the precipitate at 1050 ° C and weighed

is BaSO4.


Determination Of ZnO

After the separation of BaSO4 filtrate is evaporated to a volume of 200 ml. Neutralise with

ammonia in the presence of methyl red, add 20 ml of sulphuric acid (c) (1/2 H2SO4)

= 0.1 mol/l, [formerly 0, 1N]. The addition of sulphuric acid, c (1/2 H2SO4) = 0.1

mol/l [formerly 0, 1N], or (c) sodium hydroxide (NaOH) = 0.1 mol/l

[formerly 0 71 n], adjust the pH of the solution to a value of 2 for the control of the pH meter.

Cold is placing a stream of hydrogen sulphide precipitates zinc sulphide. After 4

hours of standing, the precipitate is filtered through a fine filter paper and

wash with cold water saturated with hydrogen sulphide. Precipitate on the filter

dissolve by adding 25 ml of hot 10% solution of hydrochloric acid.

Filter with boiling water until it gets about 150 ml of the filtrate. The filtrate

neutralize ammonia in the litmus paper, then add 1-2 g

solid urotropine to the value of the pH of the solution should be approximately 5. Add

a few drops of freshly prepared aqueous solution of xylenol 0.5%

Orange and Titrate with sodium complexone III c (C10 H14 N2 Na2 O8.2H2O)

= 0.1 mol/l, [formerly 0, 1N] until the color transition from pink to lemon



Determination Of K2O

K2O is determined by precipitation and weighing of potassium as tetrafenylboritan.

In a Platinum dish to the nearest 0.0001 g weigh about 2 g

the crushed and prosátého glass, add 2 ml of concentrated HNO3

(nitric acid), 15 ml of HClO4 (perchloric acid) and 25 ml HF

(hydrofluoric acid). Heat the water, and then on the sand

the bath. After their dense white fumes perchloric acid is

evaporate to dryness. Dissolve the addition of 20 ml of hot water and 2-

3 ml of concentrated HCl. Transfer the solution into a 200 ml volumetric flask and

make up to the mark with distilled water.

Reagents: 6% solution of sodium tetraphenylborate: dissolve 1.5 g

the reagent in 250 ml of distilled water, any light turbidity is removed

by adding 1 g of alumina. Shake for 5

minutes and filter, with the first 20 millilitres obtained again


Washing solution for the precipitate: a small amount of the potassium salt is prepared

so that in a solution of 0.1 g of KCl in 50 ml of hydrochloric acid (HCl) c

= 0.1 mol/l, [formerly 0, 1N] adds stirring the solution

of sodium tetraphenylborate to their formation of a clot. The precipitate is

filter on frit, washed with distilled water and dry in a desiccator

at room temperature. Then add 20-30 mg of the precipitate to 250

ml of distilled water and mix. After 30 minutes, add 0.5-1

(g) alumina, stir a few minutes and then


Workflow: an aliquot after acid decomposition of the corresponding

approximately 10 mg of K2O is diluted to about 100 ml., stirring

slowly add about 10 ml of precipitating agent on every

the anticipated 5 mg of K2O. Leave to stand for no more than 15 minutes, then

filter on the advance zváženém crucible of porosity 3 or 4.

Wash with washing solution and dry 30 minutes at 120 degrees C.

Conversion factor for K2O is 0.13143.



1.4.1. For the determination of any of the folders is the tolerance +/-0.1

absolute values.

1.4.2 If analysis within the tolerances, the value of the

lower than the fixed limit (30, 24, or 10%), average

from at least 3 analyses. If this average is greater than or equal to 29.95, glass

be included in the category corresponding to 30%, is higher than or equal to 23.95,

the glass shall be classified in categories corresponding to 24% and is higher than or equal to

9.95, glass is included in the category corresponding to 10%.


Other methods of chemical analysis

For the chemical analysis of the Crystal glass can be used as well as other appropriate

analytical methods, if they are proven to meet the requirements for

precision and accuracy of the results of measurement defined by subsection 1.4.1.

When you use multiple methods of measurement, or in the case of measuring according to the disputing

the first sentence is a decisive result, the one that was obtained using the methods

referred to in points 1.1 to 1.3.




The density of the

It is determined by Hydrostatic weighing with an accuracy of +/-0.01. Sample

of not less than 20 g shall be weighed in the air and then weigh the steeped

in distilled water at a temperature of 20 ° C.


Index of refraction

The index is measured by refractometer to within +/-0.001.



The Vickers hardness test with a load of 50 g.

taking the average of the 15.

1) Decree of the Minister of Foreign Affairs No. 160/1988 Coll., on International

Convention on the harmonized commodity description and coding of goods and

Protocol of amendment thereto.

§ 56 et seq. Act No. 13/1993 Coll. Customs law.

Government Regulation No. 318/1999 Coll., implementing the customs tariff.