Item No.: Y25-Ferrite-3  
Magnet Shape: arc, segment          
Material: Hard Ferrite (Ceramic)
Composite:      Fe2O3 (BaCo3 or SrO3), Fe3O4 (SrCo3, SiO2) 
Type: anisotropic or isotropic
Style:         Sintered Permanent Magnet
Grade(China Stardard):        Y25   
Detailed magnetic properties data:
Residual Magnetic Flux Density (Br): 3.6-4.0 KGs (mT):  360-400 mT
Intrinsic Coercivity Force (Hcj):    1.70-2.14 KOe    135-170 KA/m
Coercivity Force (Hcb):              1.76-2.51 KOe    140-200 KA/m
Energy Density (BH)max:              2.8-3.5 MGOe     22.5-28.0 KJ/m³
Operating Temperature:               -40 °C to +250 °C
Magnetisation Direction: Axial / Radially magnetized
Size Can be customized according to customer drawings:
Tolerance:         +/-2% mm
Delivery time           7-25 days
These high-grade ceramic magnets have been used for years for experimentation, projects, or simply to hold papers to magnetic chalk boards. They are strong and safe. The large bar magnets are great for picking up items such as paper clips or nails. All of our ceramic magnets are great for collecting the magnetite (black iron mineral) out of beach sand. (Hint: Place your magnet in a plastic zip-lock bag to avoid the mess of cleaning the magnetite off your magnet.)
Like our bar magnets, the ceramic ring magnets are perfect for a variety of experiments, projects, or simply holding papers to magnetic chalk boards. These rings fit perfectly over a standard pencil and are perfect for demonstrating magnetic repulsion.