Merwinite with Vesuvianite- Crestmore Quarries (Probable), Crestmore, Jurupa Valley, Riverside County, California, USA

Merwinite with Idocrase (Vesuvianite)
Crestmore Quarries (Probable), Crestmore, Jurupa Valley, Riverside County, California, USA
Dimensions: 5.2 × 2.8 × 2.2 cm
Provenance: Original vintage collection label, catalog no. 213, included with specimen. Original locality recorded as Riverside, California.

An interesting mineral association featuring pale blue-gray to translucent Merwinite with Idocrase (Vesuvianite). The specimen displays a coarse, interlocking crystalline texture with glassy, light-catching surfaces, accompanied by creamy white to pale yellow mineral areas and scattered darker inclusions. Its irregular form reveals an intricate mixture of crystalline aggregates, with subtle variations in color and transparency throughout.

The historic Crestmore Quarries near Riverside, California, are renowned for their remarkable diversity of calcium silicate minerals formed through high-temperature contact metamorphism. Crestmore is particularly significant as the type locality for Merwinite, a calcium magnesium silicate first described from the deposit in 1921. Idocrase, now more commonly known as Vesuvianite, is another characteristic mineral of these calcium-rich metamorphic environments. This vintage-labeled specimen represents an intriguing association of two minerals documented from the celebrated Crestmore locality, making it especially appealing to collectors of classic American minerals and historically significant mineral occurrences.