Please Heat Quartz Ceramic Crucible Bowl up Slowly and Make Sure to Glaze Bowl with Borax Before Use.Dishs are Professional for Metal Melting,Trusted by Lots of Jewelry Makers,Quality are Enough for Using Ceramic Quartz Crucible Bowl are 99.99 percent High Purity,Corrosion Resistance,Made of Durable Quartz,with Strong Thermal Conductivity,Chemical Resistance and High Temperature Resistance,can Hold 2800 Degree Temperature.The Handle Provides You a Comfortable Grip While Using it,Protect Your Hand Professional Melting Ceramic Crucible Bowl Set for Jewelry Melting Tool Also Nice for Torch Applications Gold, Brass, Bronze, Silver, Copper Molten Alloys. It is also helpful for jewelers,Metalsmiths or Blacksmiths or Chemical Refiners. 4PCS Quartz Crucible Dish Cup Bowls for Jewelry Silver Gold Casting Melting Refining with Pour Spou(about 100g Capacity),One 304 Stainless Steel Whip Tongs Handle 2A Colour:whiteandsilver Material:quartzandmetal Package Contents: 4 x Quartz Crucible Dish Cup Bowls(100G) 1 x crucible tongs 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.