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A magnetic marker for use in an article surveillance system, and an electronic article surveillance system utilizing the same are presented. The marker comprises a magnetic element including a predetermined number of microwire pieces made of an amorphous metal-containing material coated with glass a

A magnetic marker for use in an article surveillance system, and an electronic article surveillance system utilizing the same are presented. The marker comprises a magnetic element including a predetermined number of microwire pieces made of an amorphous metal-containing material coated with glass and having substantially zero magnetostriction, coercivity substantially less than 10 A/m, and permeability substantially higher than 20000, the predetermined number of the microwire pieces and a core diameter of the microwire piece being selected in accordance with a desired detection probability of the marker to be obtained in a specific detection system.

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1. A magnetic marker for use in an article surveillance system, the marker comprising a magnetic element including a predetermined number of microwire pieces made of an amorphous metal-containing material coated with glass and having substantially zero magnetostriction, coercivity substantially less

1. A magnetic marker for use in an article surveillance system, the marker comprising a magnetic element including a predetermined number of microwire pieces made of an amorphous metal-containing material coated with glass and having substantially zero magnetostriction, coercivity substantially less than 10 A/m, and permeability substantially higher than 20000, said predetermined number of the microwire pieces and a core diameter of the microwire piece being selected in accordance with a desired detection probability of the marker to be obtained in a specific detection system. 2. The marker according to claim 1, wherein the microwire piece is manufactured by a single-stage process of direct cast from melt.3. The marker according to claim 2, wherein the properties of the microwire piece are controlled by varying the metal-containing material composition and the core diameter of the microwire.4. The marker according to claim 1, wherein the microwire piece has a length substantially not exceeding 32 mm.5. The marker according to claim 1, wherein the microwire piece has a length of about 26-32 mm.6. The marker according to claim 1, wherein the magnetic element has the single microwire piece having the core diameter of about 45-60 &mgr;m.7. The marker according to claim 1, wherein the magnetic element comprises at least three microwire pieces, each having the core diameter substantially not exceeding 30 &mgr;m.8. The marker according to claim 1, wherein said metal containing material is a cobalt-based alloy.9. The marker according to claim 8, wherein said cobalt-based alloy is an alloy of Co, Fe, Si, B, Cr and Mo.10. The marker according to claim 9, wherein said cobalt-based alloy contains 68.6% Co, 4.2% Fe, 12.6% Si, 11% B, 3.52% Cr and 0.08% Mo by atomic percentage.11. The marker according to claim 9, wherein the microwire piece comprises the core made of said metal-containing material, and the glass coating, wherein the metal core and the glass coating are physically coupled to each other in several spatially separated points.12. The marker according to claim 9, wherein the magnetic element has the single microwire piece having the core made of said metal-containing material, and the glass coating, the diameter of the core being of about 45-60 &mgr;m.13. The marker according to claim 12, the diameter of the core being of about 50 &mgr;m.14. The marker according to claim 12, wherein the microwire piece has a length of about 26-32 mm.15. The marker according to claim 8, wherein said cobalt-based alloy is an alloy of Co, Fe, Si and B.16. The marker according to claim 15, wherein said cobalt-based alloy contains 77.5% Co, 4.5% Fe, 12% Si, and 6% B by atomic percentage.17. The marker according to claim 8, wherein said cobalt-based alloy is an alloy of Co, Fe, Si, B and Cr.18. The marker according to claim 17, wherein said cobalt-based alloy contains 68.7% Co, 3.8% Fe, 12.3% Si, 11.4% B, and 3.8% Cr by atomic percentage.19. The marker according to claim 15, wherein microwire piece has the core diameter substantially not exceeding 30 &mgr;m.20. The marker according to claim 19, wherein said magnetic element comprises at least three microwire pieces.21. The marker according to claim 15, wherein the microwire piece has a length of about 26-32 mm.22. The marker according to claim 17, wherein microwire piece has the core diameter substantially not exceeding 30 &mgr;m.23. The marker according to claim 22, wherein said magnetic element comprises at least three microwire pieces.24. The marker according to claim 17, wherein the microwire piece has a length of about 26-32 mm.25. The marker according to claim 1, wherein said magnetic element is accommodated between substrate and cover layers.26. The marker according to claim 25, where said substrate and cover layers are manufactured by a co-extrusion process.27. A magnetic marker for use in electronic article surveillance (EAS) system, the marker comprising a magnetic element having a single mic rowire piece, which is made of an amorphous metal-containing material with glass coating and has substantially zero magnetostriction, coercivity substantially less than 10 A/m and permeability substantially higher than 20000, a core diameter of the microwire piece being of about 45-60 &mgr;m. 28. A magnetic marker for use in electronic article surveillance (EAS) system, the marker comprising a magnetic element including at least three microwire pieces, each of the microwire pieces being made of an amorphous metal-containing material with glass coating and having substantially zero magnetostriction, coercivity substantially less than 10 A/m and permeability substantially higher than 20000, a core diameter of the microwire piece substantially not exceeding 30 &mgr;m. 29. An electronic article surveillance system utilizing a marker mounted within an article to be detected by the system when entering an interrogation zone, the system comprising a frequency generator coupled to a coil for producing an alternating magnetic field within said interrogation zone, a magnetic field receiving coil, a signal processing unit and an alarm device, wherein said marker comprises a magnetic element comprising a predetermined number of microwire pieces made of an amorphous metal-containing material with glass coating and having substantially zero magnetostriction, coercivity substantially less than 10 A/m and permeability substantially higher than 20000, wherein the marker has one of the following designs: it has the single microwire piece with the core diameter of about 45-60 &mgr;m; and it has at least three microwire pieces each with the core diameter substantially not exceeding 30 &mgr;m.