GB/T 28796-2021Craft crystal decoration (English PDF)

3.1 Craft crystal

decoration with synthetic crystal, crystal glass and natural crystal as the main raw materials, the artworks, handicrafts, decorations and daily necessities that are made by mechanical and manual processing and assembly such as thermoforming, cutting, grinding and polishing

3.3 Crystal glass

glass used to make fine utensils, art and decorations; it has high transparency, good surface gloss, is crystal clear; after thermoforming, cutting, grinding, polishing and other mechanical or manual processing, it shows good light and color characteristics

3.4 Rock crystal

A crystalline mineral with silica as the main component produced under specific natural conditions; most of the colors are colorless and transparent, purple, brown, green and so on; and most of them contain hair-like crystals, bubbles, impurities and crystal turbidity

4.1 Appearance quality

The appearance quality shall meet the requirements of Table 1.

4.2 Physical properties

The physical properties of finely ground and polished jewelry shall meet the requirements in Table 2.

4.5 Hazardous substance limit

The content of lead and cadmium in the jewelry shall meet the requirements of the limit of harmful elements of lead and cadmium in GB 28480.

5.1 Appearance quality inspection

Without the aid of an optical magnifying device, at a distance of 30cm, the test is carried out in a field of view with a black background under a fluorescent lamp with a light source intensity of 40W.

5.2 Surface processing characteristics

5.2.2 Transmittance

5.2.2.1 Instrument

Use a visible light transmittance tester.

5.2.2.3 Test operation

Boot 0.5h. After the instrument is stable, load the sample for testing.

5.2.3 Refractive index

Carry out according to the method specified in GB/T 7962.1.

5.3 Dimensional tolerance

Use a vernier caliper or altimeter with a division value of 0.02mm to measure.

5.4 Assembly requirements

5.4.1 The morphological position is visually observed against the pattern.

5.5 Hazardous substance limit

5.5.1 Sample preparation

Select 10g~30g of sample after crushing. Use an agate mortar to grind until the particle size of the sample is less than 100µm (about 180 mesh).

5.5.4 Digestion of specimen

5.5.4.1 Place the weighed specimen in a 35mL platinum crucible. Moisten with a little distilled water. Add 8mL of hydrofluoric acid and 5mL of sulfuric acid (1+1). Heat slowly in a fume hood to decompose until smoking.

5.5.5 Specimen measurement

Use atomic absorption spectrophotometry (flame method) to determine. Use the direct comparison method to perform quantification.

5.6 Color stability

Use a 40W UV lamp (wavelength 253.7nm) to irradiate at a distance of 20cm from the surface of the decoration.

6.1 Exit-factory inspection

6.1.1 Batching

Products of the same variety, type and level produced in each shift are grouped as a batch.

6.1.4 Inspection methods

Each batch of exit-factory inspection items must be accepted. If one item fails, the responsible department shall decide to scrap or re-inspect the batch after analyzing the specific failure situation. If the product resubmitted for inspection still fails to meet the requirements, the batch will be deemed rejected.

6.2 Type inspection

6.2.1 When designing a new product or improving the original product, when there is a major change in the production process, when there is a large difference between the exit-factory inspection and the last type inspection result, the type inspection shall be carried out.

6.3 Determination rules

When all inspection items are accepted, the batch of products shall be accepted. If an item in Class A fails, the batch of products shall be rejected.

7.1 Marking

The product or the outer packing box shall have the product name, product standard number, raw material name, quality grade, inspection certificate, enterprise name and address, quantity, net weight and other signs.

7.3 Transportation

The product shall not be violently collided or stressed during transportation. When loading and unloading, it shall be lightly loaded and unloaded.

7.4 Storage

Products shall be stored indoors and placed on wooden shelves or boards. Direct sunlight is prohibited. Prevent moisture and heavy pressure. The products shall not be mixed with corrosive items.