Fire Assay Crucibles

Material: Alumina Ceramic, Alumina Ceramic, Clay

Size: 20g/30g/40g/45g/50g/55g/65g/75g

Usage: fire assay, gold melting, precious metal assay

Color: Ivory

Fire assay crucibles are used in smelting of the samples. Crushed rocks, ores are mixed with fire assay flux, then heated and melted in a crucible. Gold, silver and precious metals are captured in a molten state with lead to form a lead alloy (generally called lead button, also known as precious lead), which sinks to the bottom of the crucible due to the specific gravity of the lead alloy. At the same time, the oxides and gangue of the base metals in the sample are combined with fluxes such as silica, borax, sodium carbonate, etc., to form slags such as silicate or borate, which float on them because of their small specific gravity, thereby separating the gold and silver from the sample.   

Fire Assaying is done by assay laboratories, a few leading brands are SGS, ALS, Intertek etc. who are capable of testing the purity of precious metals, say, gold, silver, and the platinum group metals.  Fire assay crucibles and the fire assaying process are also used by leading mining companies and refiners who need to analysis material ingredients by themselves.

We supply high quality , multi-use Fire Assay Crucibles—– Sizes available include 30, 40, 50, 55 and 65g and we can produce the special size according to customer’s requirement.  All crucibles can be packed in crate or cartons with pallet.

Product Instruction

Our universal fire assay crucibles material of construction is fireclay mixed with other refractory materials. They withstand temperatures up to 1300`C. This composition and their design give them an excellent resistance against flux attack, erosion, cracking and thermal shock.

Product Feature

Our crucibles have a longer lifer under harsh working conditions.

They have a high resistance to thermal shock, produce a faster fusion, constant melting speed .

Another important feature is that they are very stable based on their wide bottom which is particularly relevant for furnaces that have an irregular ground due to flux attack and erosion.

Our crucibles design allows nesting, and obtain an optimal space utilization in the warehouse, and minimal transport costs to any location.

Last but not least, their dense body also minimizes absorption losses.

Details of Chemical Content

Product: Fire Assay Crucible
Production Method: Roller Forming
Typical Chemical Analysis
SiO2 54.06%
Al2O3 37.80%
CaO 0.47%
Fe2O3 1.54%
TiO2 1.35%
K2O 0.72%
MgO 0.00%
Na2O 0.00%
Working Temperature 1000℃-1150℃
Firing Temperature 1400℃
Usage time 3-5
Specific Gravity 2.3
Porosity 25%-26%

Data of Dimensions

SCHEMATIC

OH: out height
TOD: top out diameter
TID: top inner diameter
BOD: bottom out diameter

NO. GEM30 GEM40 GEM45 SGSNA 45 GEM50 SGSNA50 GEM65 GEM75 GEM75H 210 TN4
VOLUME(ml) 200 305 440 440 440 440 570        
OH(mm) 105±2 135±2 160±2 155±2 150±2 145±2 165±2 180±2 210±2 210±2 148±1
TOD(mm) 82±2 88±2 90±2 88±2 105±2 105±2 105±2 120±2 125±2 125±2 114+1
TID(mm) 74±1 78±1 79±1 80±1 90±1 90±1 92±1 106±2 105±2 102±2 94±1
RIM TH 5±0.5 6+0.6 6.5±0.6 5±0.5 8.5+0.8 7.5±0.7 7.5±0.7 7.5±0.7 7.5±0.7 7.5±0.7 10±0.7
BOD(mm) 54±1 55+1 58±1 57±1 56±1 57±1 55±1 70±1 61±2 61±2 77±1
QTY/20’FCL 48620 36960 30000 32800 30000 30600 27000 17280     21600
NEW QTY/20’FCL 60840 43200 34320 34320 30600 30600 28800        

Standard package is crate or carton.

We manufacture Fire Assay Crucibles of various standard sizes and it can be customized as per demands of the client’s specification and requirement.

Applications

1. Precious metal analysis

2. Mineral assaying

3. Mining laboratory

4. Laboratory Testing

5. Fire Assaying

6. Gold Assaying

Package

wooden cases, cartons with pallet