Usage: Suitable for Refining Casting Molding /Metal /Gold/Silver/Brass/Copper/Alloy etc. Material:Made of premium ceramic, purity, corrosion resistance, high strength, high heat resistant, high shock resistance. Widely used: Widely used in electric light, semiconductors, optical communications, , metallurgy, building materials, chemical, mechanical, electrical, environmental protection and other fields. Design: Designed with tapered sides and a pour spout for easy material removal. Specifications: Capacity:100,150, 250g, 400g,500g Five size as bellow: Crucible Bowl(100g): Outer Diameter: 52 mm; Inner diameter: 45mm; Height: 21mm; Net weight: 30g Crucible Bowl(150g): Outer Diameter: 60 mm; Inner diameter: 47mm; Height: 25mm; Net weight: 36g Crucible Bowl(250g): Outer Diameter: 70 mm; Inner diameter: 60mm; Height:25mm; Net weight:. 52g Crucible Bowl(400g): Outer Diameter 75 mm; Inner diameter: 65mm; Height: 32 mm; Net weight: . 80g Crucible Bowl(500g): Outer Diameter: 83 mm; Inner diameter: 70 mm; Height: 36 mm; Net weight: . 94g Unit conversion: 1mm = 0.0393inch Note: Before the gold and silver melt, borax should be placed at the bottom of the bowl to prevent the gold and silver from melting and sticking to the bottom. The melting bowl is easy to absorb moisture, and it is preheated and gradually heated before use to prevent water from chilling and bursting. Material: Metal colour: As shown Package Contents: 5 x quartz silica melting crucible (100/150/250/400g/500g) 2 x tweezers (pointed and elbowed) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.