Janka hardness around 1,250 lbf, specific gravity 0.65 to 0.68, dried to 8-10% for European interiors. Harder than plain birch, softer than sugar maple, and unforgiving of a dull blade.

Wipe a damp cloth across a rough-sawn face and the figure lights up straight away, because interlocked fibres absorb water at different rates. Bark, end grain and honest photographs of all sides catch the rest of the mislabelling.

Forty percent usable material out of a log that looked perfect from the outside. Add winter felling at minus twenty, hand grading and eight to twelve months of drying, and curly birch pricing stops looking arbitrary.

Masur is Swedish and German, Karelian points to a region, visakoivu is what a Finnish forest owner says. The name tells you where your seller learned the trade, not whether the wood is any good.

Betula pendula var. carelica is a genetic variant of silver birch, not a disease or a wound. One to two percent of trees carry it, and bumpy bark is how you spot one standing.