Red jasper (likely brecciated jasper)

Opaque brick-red to brown, with pale angular veining and a dull to waxy luster. Quartz hardness is about 6.5–7 Mohs; no obvious cleavage, conchoidal-to-uneven fracture, and typical specific gravity around 2.5–2.7.

Forms when silica-rich fluids cement and replace sediments or volcanic material, with iron oxides producing the red color; brecciation can create the angular pale fragments. It is generally not age-diagnostic and may form in many geological periods.

Used for cabochons, beads, carvings, polished slabs, and ornamental stone; occasionally used as a durable decorative aggregate.

The specimen’s angular pale cracks/fragments strongly suggest brecciated jasper rather than uniform red chert. Exact identification would benefit from a fresh surface, streak test, and hardness test.

Common in silica-rich veins and altered volcanic or sedimentary rocks worldwide. In the Budapest-area region, red jasper/chert and iron-stained siliceous rocks are plausible; the photograph alone cannot establish a precise locality. It should scratch glass but not quartz, and it leaves little or no streak on unglazed porcelain.