Laboratory crystallising dishes: how can crystallisation, evaporation or drying be promoted?

The crystallising dish is the trusted ally of chemists and analysts to carry out slow crystallisation, concentrate a solution by evaporation or dry a solid flat. Its wide, shallow geometry maximises surface area, accelerating evaporation while offering excellent visibility of nucleation and crystal growth. In borosilicate glass or stainless steel, it is selected according to the target temperature, the chemistry involved and the required robustness. A pouring spout, beaded rim, graduations or a lid complete a simple, precise and durable tool.

What are the different types of crystallising dishes?

Three families cover the bulk of requirements. The crystallising dish in borosilicate glass combines chemical inertness, transparency and dimensional stability. Ideal for recrystallisation and in situ observation, it tolerates moderate heating (hotplate with support) and controlled variations, while avoiding sudden thermal shock.

Key selection criteria: volume (50 mL to 1 L), chemical compatibility, accessories (pouring spout, lid), readability (graduations), ease of cleaning and thermal resistance. Quick comparison:

Type	Thermal resistance	Uses / Benefits
Borosilicate glass	Up to ~500 °C (moderate heating, avoid thermal shock)	Recrystallisation, observation; transparency, chemical inertness

In which fields is a crystallising dish used?

• Life sciences and pharmaceutical: purification by recrystallisation of compounds, control of polymorphs, gentle drying of intermediates.
• Chemistry (organic and analytical): concentration of extracts, solvent evaporation, observation of nucleation.
• Agri-food: crystallisation trials (sugars, salts), solubility determination, sample preparation.
• Cosmetics: characterisation of crystallisable ingredients, stability of raw materials.
• Environment: evaporation of aliquots for residue screening, preconcentration prior to analysis.
• Quality control and R&D: flat drying, recovery of solids, comparative crystal-growth tests.
• Teaching: crystallisation demonstrations, enhanced safety with plastic versions.

The different types of crystallising dishes available

Frequently asked questions about laboratory crystallising dishes

What’s the difference between a crystallisation dish and an evaporating dish?
A crystallisation dish is wider and shallow to promote crystallisation and make observation easier. An evaporating dish is designed for rapid evaporation and can withstand more vigorous heating.

Can I heat a glass crystallisation dish directly over a flame?
No. Use a hotplate with a support (e.g., gauze, sand bath) and avoid thermal shock.

What volume should I choose?
Select 3–5 times the initial solution volume to prevent boil-overs and ease handling, while keeping a large evaporation surface.

How can I limit contamination during evaporation?
Use a lid or a watch glass set at an angle to protect the contents while allowing vapours to escape.

Cleaning tips?
Rinse straight away, use a neutral detergent, and brush gently.

Can I measure an accurate volume in it?
The graduations are indicative only. For accuracy, use volumetric glassware (volumetric flasks, measuring cylinders), then transfer to the crystallisation dish.