Diamond Symbols

Diamond shapes occupy a distinctive niche in Unicode's symbol repertoire. Rotated 45 degrees from a square, the diamond (or lozenge) appears everywhere from playing cards to mathematical notation, from road signs to UI design. Unicode encodes filled and outline diamonds in multiple sizes, playing-card suit diamonds, lozenges, and several mathematical diamond operators. This guide catalogs every diamond-shaped character in Unicode, explains the differences between visually similar variants, and provides practical copy-paste references.

Quick Copy-Paste Table

Geometric Diamonds (U+25C6–U+25CA)

The Geometric Shapes block contains the core diamond characters used in general typography and design.

◆ Black Diamond (U+25C6) and ◇ White Diamond (U+25C7)

These are the fundamental diamond pair. ◆ is a solid filled diamond, and ◇ is its outlined counterpart. As with all geometric shapes in Unicode, "black" means filled and "white" means outlined.

◆ is one of the most popular bullet point alternatives. It adds visual weight and distinction compared to the standard bullet (•) while remaining cleanly geometric:

<ul style="list-style: none">
  <li>&#x25C6; First item</li>
  <li>&#x25C6; Second item</li>
  <li>&#x25C6; Third item</li>
</ul>

◈ White Diamond Containing Black Small Diamond (U+25C8)

This composite character renders as an outlined diamond with a smaller filled diamond centered inside. It is useful for creating visual hierarchy — for example, ◈ for top-level items and ◆ for sub-items in a styled list.

◊ Lozenge (U+25CA)

The lozenge is geometrically similar to the white diamond but has a slightly different heritage. In typography, "lozenge" traditionally refers to a narrow, elongated diamond shape used as a bullet or separator. In practice, many fonts render ◊ identically to ◇, but the intended distinction is that the lozenge has a taller, narrower aspect ratio.

The lozenge has a particular connection to pharmaceutical notation, where it indicates tablet form, and to heraldry, where the lozenge is a standard charge (shape used in coat of arms design).

Playing Card Diamonds

Unicode encodes card suit symbols in the Miscellaneous Symbols block:

The naming here is counterintuitive: ♦ (U+2666) is called "Black Diamond Suit" even though the diamond suit is traditionally rendered in red in Western playing cards. The "black" in the Unicode name refers to the filled glyph style, not the color. In a card game context, you would apply red coloring via CSS:

<span style="color: red">&#x2666;</span>  <!-- Red filled diamond -->
<span style="color: red">&#x2662;</span>  <!-- Red outline diamond -->

Emoji Diamonds

The emoji block introduces colored diamond characters that render with platform-specific styling on mobile devices:

These emoji diamonds are widely used in social media and messaging for visual emphasis. 🔹 and 🔸 work well as bullet markers in platforms that support emoji but not custom CSS, such as Twitter/X bios and Slack messages.

Mathematical Diamond Operators

Mathematics uses diamond shapes for several distinct purposes:

The diamond operator ⋄ (U+22C4) is particularly important in mathematics and computer science. In modal logic, the diamond operator represents "possibility" — if ⋄P is true, then P is possible (as opposed to the box □ which represents necessity). In lattice theory, ⋄ may denote the join operation.

% LaTeX usage
\diamond    % produces ⋄
\Diamond    % produces ◇ (from amssymb)
\lozenge    % produces ◊ (from amssymb)

◆ vs ♦ vs ◊ — Choosing the Right Diamond

Three diamond characters are frequently confused:

In many fonts, all three render identically. When choosing:

• Use ◆/◇ for UI elements, bullet points, and general design.
• Use ♦/♢ when explicitly referencing playing cards or card games.
• Use ◊ in typographic or mathematical contexts where "lozenge" is specified.

Keyboard Shortcuts and Input Methods

Diamond Characters in Programming

Diamonds appear in several programming contexts:

# Python: using diamond symbols
DIAMOND_BULLET = "\u25C6"  # ◆
DIAMOND_SUIT = "\u2666"    # ♦
LOZENGE = "\u25CA"         # ◊

# Formatting a list with diamond bullets
items = ["Alpha", "Beta", "Gamma"]
for item in items:
    print(f"  {DIAMOND_BULLET} {item}")

In flowchart notation, the diamond shape represents a decision node. While flowcharts are typically drawn graphically, text-based diagram tools like Mermaid use diamond syntax:

graph TD
    A[Start] --> B{Decision}
    B -->|Yes| C[Action]
    B -->|No| D[End]

The curly braces {} in Mermaid produce a diamond/rhombus node for the decision.

Key Takeaways

• Unicode encodes 16+ diamond-shaped characters across Geometric Shapes, Miscellaneous Symbols, Mathematical Operators, and emoji blocks.
• ◆ (U+25C6) is the go-to geometric diamond for bullets and UI; ♦ (U+2666) is for playing card contexts; ◊ (U+25CA) is the typographic lozenge.
• Playing card suit names use "black" for filled glyphs — ♦ is called "Black Diamond Suit" despite diamonds being traditionally red in cards.
• Emoji diamonds (🔶🔷🔸🔹) provide colored alternatives for social media and messaging platforms.
• The diamond operator ⋄ (U+22C4) is semantically distinct from geometric diamonds and is used in modal logic and lattice theory.
• On macOS, Option + Shift + V inserts the lozenge ◊ directly.