Undefined, 2020

by Yuiko Ráyka

Painting : resin, gold leaf

30 x 30 x 2.5 cm 11.8 x 11.8 x 1 inch


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About the artwork


Unique work


Hand-signed by artist


Sold with certificate of Authenticity from the gallery

Invoice from the gallery


Painting: resin, gold leaf

Dimensions cm inch

30 x 30 x 2.5 cm 11.8 x 11.8 x 1 inch Height x Width x Depth


Not framed


Abstract artworks

Eastern Art

Abstract art

Asian art

Japanese Art



Artwork sold in perfect condition

Artwork location: Belgium

Mixed media 
23.4K Japanese genuine gold leaf
Resin, fluorescent white paint, canvas

Available in gallery

• This series of works is developed mainly in mixed media. The improvised forms in resin express the unclassifiable and undefinable, while the gold leaf represents the strength of unknown energy.

• In the series, "Unknown Power," I focus on the unknown of the world and ourselves, and its unlimited energy. The improvisatory forms made of resin manifests the concept of the unknown, and the gold leaf applied to its surface expresses the unknown energy's strength and power.

• Believing in the unknown power of the world and ourselves can extend the boundaries of our perception and bring about a new understanding and hope for the world and ourselves.

• There are things in this world that cannot be "defined" or "categorized."
Each of us, each thing that exists in this world, and even the world itself, is inherently more diverse, more unknown, and more full of possibilities than we realize.
Believe in the unknown within yourself. If you do, the world will become more wonderful.

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About the seller

Art Yi Gallery • Belgium

Artsper seller since 2023

Vetted Seller

Imagine it at home

Yuiko Ráyka, Undefined

Yuiko Ráyka

Japan  • 1978


• Yuiko Ráyka is a Japanese contemporary artist, born and currently lives in Tokyo, Japan.

• She works in mixed media, ligth art, installations, media art, NFTs, and expression utilizing VR and the metaverse.

• Her body of work is to focus on the unknown potential of each of us as human beings and our evolving spirits toward a new era. She attempts to create multidimensional expressions that work in the realm of human consciousness by combining physical experiences with non-physical medium. In recent years, she has been creating interactive installations that emphasize experience and media works utilizing VR, Metaverse and NFT.

• Graduated from Kyoto Seika University, Faculty of Art, BFA in painting in 2003. Studied at the Australian National University School of Art & Design, majoring in Gold & Silversmithing as an exchange student in 2001 - 2002. During her student days, she was exposed to a variety of materials and tried her hand at expression through two-dimensional, three-dimensional, and installation works.

• After graduating from university, she moved to Germany in 2004 and worked as a graphic designer at a video production company in Dusseldorf.

• Upon returning to Japan, she worked as a graphic designer then after she started her career as an illustrator in 2010 (under a different name). Her works have been used for the cover of the paperback edition of Sayaka Murata's "Hoshi ga sū mizu" (Kodansha), NHK TV program character design, fashion brand "deep sweet easy", Excel Hotel Tokyu guest room artwork, and stage art etc.

• In 2014, she shifted her main focus to artistic activities and began creating mixed media and installations. Currently, she has three series: "SELFVERSE," an experiential installation, "SOUL GEMS," an installation and media art, and "Unknown Power," a mixed media series, which have been shown at art fairs and exhibitions around the world.

• Since 2021, she has been presenting digital works as NFTs (under the name AURORA) and participating in many national and international events and projects.

• In 2022, she began embarking on an expression utilizing VR and the metaverse.


2021【NFT】#BigBangNFT Competition winner

2019  FLAG prize
2019  AFAF WARD 2019 finalist
2013  Taipei International art competition 2013 finalist
2012  WONDER SEEDS 2012

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