How can I check the phase of a Doppler knife before buying?

Use Steam's built-in inspect feature or a third-party tool like CSFloat Market Checker. The pattern index is visible in the item info. On CSBoard, you can discuss the phase with the seller directly via the P2P trade chat and request screenshots before committing. Always verify the pattern index matches the advertised phase.

Which Doppler phase is the most expensive?

Sapphire (pure blue) and Ruby (pure red) are the most expensive, often ranging from $2,000 to over $8,000 for a Karambit or M9 Bayonet in Factory New. Black Pearl is the rarest but can be slightly less liquid than Sapphire. Among regular phases, Phase 2 (pink) commands the highest premium, while Phase 4 (blue) is a close second.

What's the difference between Phase 2 and Ruby?

Phase 2 is a regular Doppler phase with a dominant pink/purple hue and some black accents. Ruby is a special phase with a pure, solid red blade and no black. Ruby is much rarer and significantly more expensive. Phase 2 is a common mistaken substitute for Ruby, so always check the pattern index to confirm.

Do Black Pearl knives actually have any color?

Yes, Black Pearl features a dark, metallic base with subtle shifts of purple, green, and blue depending on the light. It's not solid black; it's a complex, oily finish that's highly prized by collectors. The pattern index is unique and does not fall into the 0-1000 range of regular phases.

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2026 Edition · Trading Guide

CS2 Doppler Phases: Complete Guide to Phase 1-4, Ruby, Sapphire & Black Pearl

TL;DR

▸Doppler finishes come in 7 phases: Phase 1-4, Ruby, Sapphire, and Black Pearl — each with a distinct color palette.
▸Phase 2 (pink-dominant) and Sapphire are the most liquid, while Black Pearl is the rarest, often exceeding $2,000 in Factory New.
▸CSBoard charges 0% for deposits and direct item-for-item exchanges without money. P2P marketplace sales carry a 2% selling fee. Instant sell is a separate buyout offer; check its quote and the chosen payout method’s fees and timing before confirming.
▸You can inspect any Doppler knife live on CSBoard at /en/items/karambit-doppler-factory-new — no middlemen, peer-to-peer trades.
▸Pattern index determines the phase: 0-400 (Phase 1), 401-600 (Phase 2), 601-800 (Phase 3), 801-1000 (Phase 4), with special IDs for Ruby, Sapphire, Black Pearl.

Always verify the phase before buying

Inspect the knife in-game or use Steam's built-in preview to check the pattern index. CSBoard lets you trade directly with the seller — ask for an in-game screenshot to confirm the color mix before finalizing the P2P deal.

Top 5 Doppler Phases for Investment in 2026

Doppler Phase Color & Price Reference

Phase	Dominant Colors	Price Range (FN)	Rarity
Phase 1	Black, purple, small blue	$400 – $800	Common
Phase 2	Pink, purple, minimal black	$800 – $2,000	Uncommon
Phase 3	Blue, green, black	$400 – $700	Common
Phase 4	Deep blue, minimal black	$600 – $1,500	Uncommon
Ruby	Pure red	$2,000 – $6,500	Rare
Sapphire	Pure blue	$2,500 – $8,000+	Rare
Black Pearl	Dark multicolor	$1,500 – $3,500	Very Rare

Popular Doppler Knives on CSBoard

Frequently Asked Questions

A Doppler finish is a rare knife skin that displays a swirling pattern of colors. The pattern index (0–1000) determines the phase: Phase 1 (0-400) is black/purple, Phase 2 (401-600) is pink, Phase 3 (601-800) is blue/green, Phase 4 (801-1000) is deep blue. Special pattern IDs produce Ruby (red), Sapphire (blue), or Black Pearl (dark multicolor). The phase drastically affects the visual appearance and market price.

Find Your Perfect Doppler Phase on CSBoard

CSBoard charges 0% for deposits and direct item-for-item exchanges without money. P2P marketplace sales carry a 2% selling fee. Instant sell is a separate buyout offer; check its quote and the chosen payout method’s fees and timing before confirming.

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