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Which metals have a hexagonal close-packed crystal structure?

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Diagram of a zinc-lead blast furnace system showing ore and coke entering through charge hoppers, with labeled furnace, air preheater, blower, taphole for slag and lead bullion, and a connected lead-splash condenser using rotors to separate and cool lead and zinc, with pathways for molten metals and off-gas. — metallurgy A zinc-lead blast furnace and lead-splash condenser. This technology is utilized mainly for producing zinc while managing both lead and zinc from raw materials, a technique that was highly influential in 20th-century smelting.

In metallurgy, the hexagonal close-packed (hcp) crystal structure is one of the most common arrangements for metallic elements, characterized by an $A B A B . . .$ stacking sequence of atomic planes. In this structure, each atom has 12 nearest neighbors, and the spheres occupy 74 percent of the total volume.12

There are 32 metals that exhibit the hcp lattice. Notable examples include:1

Magnesium2
Cadmium12
Zinc12
Alpha titanium2
Holmium, erbium, thulium, and lutetium (which are monomorphic with the hcp structure)3

Some metals, such as samarium and ytterbium, also exhibit hcp structures depending on temperature or as part of their allotropic behavior. Because some elements can crystallize in multiple forms, the total count of metals with specific structures often overlaps.31