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How do the melting points of alkaline-earth metals compare with those of alkali metals?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — alkaline-earth metal Modern version of the periodic table of the elements (printable).

The melting points of alkaline-earth metals are higher than those of the corresponding alkali metals.1

While alkali metals are characterized by having some of the lowest melting points of any non-gaseous group in the periodic table—ranging from 179 °C for lithium to 28.5 °C for cesium—alkaline-earth metals are generally harder and possess higher melting points. For instance, magnesium has a melting point of 650 °C, and beryllium has the highest in its group at 1,287 °C.231

The lower melting points of alkali metals are a direct result of their loose crystallographic arrangement and the weak bond energies associated with their large interatomic distances. In contrast, the alkaline-earth metals exhibit stronger metallic bonding, contributing to their increased hardness and higher melting points compared to their neighbors in Group 1.213