The BCA Polycarbonate Crystal Card is a Lexan card that gives you a surface for looking at snow grains and sizing them against a grid. It also carries a ruler and a slope index for reading slope angles off a topographic map.

What it's for

In a snow pit you scrape grains from a layer onto the card, then judge their size against the grid and identify the grain type. Grain size and type help you understand how a layer formed and how it may behave.

How it works

Grid: a printed grid for sizing grains

Reference: snow crystal classification symbols and snow pit reference sheets under a protective clear coat

Translucent section: a blue translucent area and an area free of graphics make grains easier to see

Slope index: lets you work out slope angle from the contour spacing on a topographic map

Polycarbonate: does not conduct heat into the grains, so they do not melt on the card. BCA says the polycarbonate card suits sunny climates because it holds less heat than its aluminum card

Features

• Ruler: metric
• Edge: beveled

Compatibility

• BCA Snow Study Kit: the crystal card fits inside the kit

Setup and installation

• Training: reading a snow pit is a skill taught in avalanche courses. OMG runs AIARE avalanche courses

Specs

• Size: 6 x 4 in (15 x 10 cm)
• Weight: 1.2 oz (35 g)
• Material: Lexan polycarbonate
• BCA model: C2018003

Warning

This product can expose you to chemicals including Bisphenol A (BPA), which is known to the State of California to cause birth defects or other reproductive harm.