Strengthened glass with deep depth of compression

A glass article having a thickness t, the glass article comprising:

• a compressive layer having a compressive stress CS in a range from about 500 MPa up to about 1200 MPa at a surface of the glass article, wherein:
• a. the compressive layer extends from the surface to a depth of compression DOC, wherein DOC≥0.1·t when t<0.5 mm and DOC≥50 μm when t≥0.5 mm, and wherein the compressive layer has a compressive stress profile;
• and
• b. the compressive stress profile comprises:
• i. a first portion b extending from the surface to a depth db and having an average slope mb, wherein −40 MPa/μm≥mb≥−200 MPa/μm,
• ii. a second portion c extending from a depth dc to the DOC and having an average slope mc, and
• iii. a transition region extending from db to dc having a slope that transitions from slope mb to slope mc,
• wherein the first portion b is linear such that
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• where σ″(x) is the second derivative of the stress profile in the first portion b with respect to depth x and σ′(x) is the first derivative of the stress profile in the first portion b with respect to depth x.