These are finest quality, highly pure, dewaxed shellac flakes and they produce a wonderfully transparent, very hard surface. The super blonde flakes are very pale, the lemon brightens and accentuates figure and the garnet adds warmth and character. You can mix them together, either dry or dissolved, to adjust the results and get exactly the colour you want. In their dry form they have a shelf life of years. Once dissolved shellac will degrade over a period of about six months (although old shellac can still be used as a sealer for the ends of boards in storage).
Shellac is a fantastic finish, it is non-toxic, easy to apply, repairable, adjustable for depth of colour, dries in minutes, can be applied over oil. It's not just for French polishing either. You can apply it with a brush or polishing mop, spray it or just rub it on with a lint free cloth. A few layers of shellac over a well dried oil finish will seal the surface and allow varnishes to be used over the top, it can also be used as a sanding sealer
Shellac is usually mixed in 'pound cuts' - i.e. a two pound cut = 2lb of shellac in a gallon of meths or alcohol. That's far more than any of us are likely to need, but if you want to make smaller quantities it's much easier to subdivide if you go metric.
1 gallon = 4.54 litres
1lb = 453g
So 10g of shellac in 100ml of meths is a 1lb cut, 20g in 100ml is a 2lb cut and so on.
To prepare the flakes, crunch them up and pour them into a bottle, add the appropriate amount of methylated spirits and let them dissolve over a day or so, giving them a shake occasionally. I usually make up a strong solution and then dilute it with more meths as required.