The khatem: the 8-pointed star at the heart of Moroccan tile work

The khatem, the 8-pointed star formed by overlapping two squares offset by 45°, is the single most iconic motif in Moroccan and Andalusian Islamic geometric art. It anchors more than 140 documented patterns in the Wichmann and Wade octagonal corpus. It appears on the walls of the Alhambra, in every major Moroccan madrasah, and across the broader Maghreb tradition from the 12th century to the present. It also pre-dates Islam by centuries, appearing in Roman mosaics from the 2nd century CE onward.

Two things this post will and won't do. It will explain the geometry, the history, and the role the khatem plays in the larger pattern tradition. It won't claim mystical or symbolic meaning for the form, because the surviving primary sources don't support such claims for the classical pattern tradition. The Wichmann and Wade book is explicit on this point: classical Islamic geometric patterns, including the patterns built around the khatem, were "free of any symbolic meaning." They were valued for their order, their skill, and their beauty, not for what they were thought to represent.

The geometry

The khatem is constructed by overlapping two squares rotated 45° relative to each other. The result is a regular 8-pointed star with vertex angles of 90° at the four square corners and inner angles of 45° at the cusps where the points meet.

Mathematically, the khatem is a regular star polygon — specifically, the regular 8-pointed star, denoted {8/2} in Schläfli notation (though some mathematicians reserve {8/2} for the compound of two squares and prefer to write the connected star polygon as {8/3}). The form has 8-fold rotational symmetry around its centre and 8 lines of reflective symmetry.

What makes the khatem so useful as a pattern anchor is that the 90° and 45° angles work cleanly in tessellation. The internal angles of the khatem fit precisely with squares (4 squares can surround a khatem with no gaps), with other 8-pointed stars (8 khatems can interlock around a central point), and with kite-shaped tiles (the canonical Moroccan pattern uses a khatem surrounded by hexagonal petals and kite-shaped tiles to fill the gaps).

The Roman precedent

Worth being clear that the khatem isn't an Islamic invention. The form appears in Roman mosaics from at least the 2nd century CE. The Tipasa mosaic in Algeria, dated roughly to the 2nd–3rd century, includes a clear khatem at the centre of a complex tessellated panel. Similar forms appear in mosaics from Antioch, North Africa, and across the Roman Mediterranean.

When the Islamic geometric tradition consolidated in the 11th and 12th centuries (see the Sunni Revival post), craftsmen working in Morocco and Andalusian Spain inherited the khatem as a form that pre-existed Islamic civilization. What they did was build a comprehensive pattern system around it, developing the octagonal family that Wichmann and Wade catalog at 140+ documented patterns.

This kind of inheritance and transformation is typical of Islamic decorative art. Many of the geometric forms used in Islamic patterns have pre-Islamic roots; the distinctively Islamic contribution is the systematic development of pattern families and the mathematical rigor with which the forms were combined.

The Moroccan-Andalusian concentration

The khatem-anchored pattern family is dominated by two regions. Of the 140+ documented patterns in the Wichmann and Wade octagonal corpus, 21% come from Morocco and 18% come from Spain. Together that's more than a third of the global corpus. The rest are distributed across Egypt, Iran, India, Syria, Central Asia, and Turkey, but in those regions other geometric traditions (girih and kashi in Iran, Mamluk hexagonal and 12-pointed work in Egypt) tend to dominate.

The reason for the Moroccan-Andalusian concentration is partly cultural and partly material. The 90° and 45° angles of the khatem family are particularly well-suited to cut tile mosaic, which is the dominant decorative medium of the Maghreb tradition. The pattern logic and the production technique evolved together; the patterns that worked in zellij became the patterns Moroccan craftsmen built their tradition around.

For more on the technical tradition, see what is zellij. For the regional context, see Moroccan Islamic art — the Maghreb tradition.

The famous khatem-anchored patterns

A few specific examples worth knowing about:

The Sala del Mexuar dado pattern at the Alhambra. Built around an 8-pointed central star with surrounding hexagonal petals and kites. Wichmann Chapter 8 works through the complete geometric construction.

The Bou Inania zellij in Fez. The 14th-century Marinid madrasah uses several khatem-anchored patterns in its tile dadoes, each slightly different but all drawing on the same octagonal family.

The Saadian Tombs zellij in Marrakesh. 16th-century Saadian work uses khatem-anchored patterns in larger formats than the earlier Marinid work, demonstrating the scale flexibility of the pattern family.

The Patio de los Leones tile at the Alhambra. The most famous space in the Alhambra includes khatem variants in its tile dadoes, alongside related decagonal work in carved stucco.

Patterns built around the khatem also appear in less expected places. Tipasa, as noted. Various Mamluk Cairene monuments. The Alaouite-era monuments of Morocco (17th–19th centuries). A handful of patterns in the Ottoman tradition. The form travels, even if the dense pattern family concentrated in the Maghreb.

What the khatem doesn't mean

A note worth being explicit about. Internet sources will tell you the khatem represents the eight gates of paradise, the eight angels carrying the throne of God, the harmony of the four elements with the four cardinal directions, the union of the material and the spiritual, the seal of Solomon, or various other symbolic readings. These claims show up in design blogs, tourist materials, and even some popular books on Islamic art.

The honest scholarly position is that none of these symbolic readings is well-supported by primary sources from the period when the Maghreb pattern tradition was developing. The Wichmann and Wade book treats the patterns as mathematically interesting forms valued for their order and skill, not for symbolic content. Necipoğlu's Topkapı Scroll takes the same position. Tabbaa's work on the Sunni Revival treats the geometric tradition as part of a religious-political program but doesn't read individual motifs as carrying specific symbolic meanings.

This matters because the symbolic readings can mislead buyers and viewers about what they're encountering. A khatem in a zellij panel isn't telling you something specific. It's part of a beautifully ordered composition, a demonstration of craft, an expression of cosmic equilibrium (mizan, in the general Islamic sense — see why there are no figures in Islamic art). The meaning, to the extent there is one, is the order itself, not a specific message encoded in the form.

The contemporary symbolic readings emerged largely in the 20th century, often through Sufi-inflected interpretations that aren't well-grounded in the historical record of the classical pattern tradition. They're not necessarily wrong as personal or contemporary readings; they're just not what the classical tradition was doing.

FAQ

What is the khatem?

The khatem, also spelled khatim, is the 8-pointed star formed by overlapping two squares offset by 45°. It is the most iconic geometric motif in Moroccan and Andalusian Islamic art, anchoring more than 140 documented patterns in the Maghreb tradition.

Does the khatem have symbolic meaning?

Classical Islamic geometric patterns, including those built around the khatem, were valued for their order, skill, and beauty rather than for specific symbolic meanings. Various symbolic readings have been proposed by 20th-century writers (often Sufi-influenced) but are not well-supported by primary sources from the period when the Maghreb pattern tradition was developing.

Is the khatem a uniquely Islamic form?

No. The 8-pointed star formed by two overlapping squares appears in Roman mosaics from at least the 2nd century CE, predating Islam by centuries. Islamic craftsmen in the Maghreb developed a comprehensive pattern system built around the khatem, but they inherited the form itself from earlier traditions.

Where can I see the khatem in famous Islamic monuments?

The Alhambra in Granada contains many khatem-anchored patterns, especially in the Sala del Mexuar tile dadoes. The Madrasa Bou Inania in Fez has prominent khatem zellij. The Saadian Tombs in Marrakesh, the Madrasa al-Attarine in Fez, and most Marinid and Saadian Moroccan monuments use khatem patterns extensively. Beyond the Maghreb, the form appears in scattered examples across Mamluk Cairo, the Ottoman tradition, and elsewhere.

Sources

• Wichmann, Brian, and David Wade. Islamic Design: A Mathematical Approach. Springer, 2017. Glossary entry on khatem; Chapter 7 (introduction to the octagonal set); Chapter 9 (extended catalog).
• Castéra, Jean-Marc. Arabesques: Decorative Art in Morocco. ACR Edition, 1999.
• Necipoğlu, Gülru. The Topkapı Scroll. Getty Center, 1995.
• For the Tipasa mosaic and Roman precedents, see standard art-historical surveys of Roman mosaic.