CoE does not determine compatibility. Of course Coefficient of Expansion (CoE) increases the chance of compatibility, but when it is understood that it is CoE that is manipulated to give an equal but opposite force to the viscosity, you realise that CoE is a variable measurement of compatibility rather than a constant. The formulation for each colour of glass has to have a different rate of contraction to balance the force of viscosity.
Each manufacturer uses a range of CoEs to make their glass fusing compatible. Spectrum once noted that their fusing glass varied by 10 points, and since Oceanside is using the formulations from Spectrum it is most likely the same is true for their glass. So if 96 were the midpoint of the CoEs used by Oceanside, the range is 91 to 101. Bullseye has stated their CoE range is 5 points, and that when taken to the next decimal point, it is closer to 91 than 90. Again, assuming that 90.5 is the midpoint, their range is from 88 to 93. Theoretically it would be possible to find a 96 glass compatible with Bullseye.
Each manufacturer will formulate their colours differently (because they don't know the exact formulations of others' glass), and so a glass in their "96" range, for example, may vary enough from another's to be incompatible. We practitioners can't know what or which variations there are without testing the compatibility. And that's why I stick to one manufacturer, even though I may like colours from other manufacturers. Anyway, it is possible to combine colours in one manufacturers line to imitate colours in another's, and there are people who have done the work to determine combinations to provide a wide range of shades and tones. For example, Kim Brill has done it for Bullseye sheet glass and for powders.
Since CoE and Compatibility are not the same thing, it is risky to assume all glass labelled with the same CoE number will always be compatible.
More details about CoE and compatibility.
Cautions about compatibility of glass with the same CoE number.
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